The Object of Service Design - Ricerca sull'intelligenza artificiale specializzata al MIT

The Object of Service Design
Fernando Secomandi, Dirk Snelders

introduzione
Recent decades have witnessed a steep increase in service research
springing from disciplines as diverse as economics, management,
and engineering. For the most part, this interest is a response to the
expansion of the service sector in the last century and the consequent
penetration of services in almost all areas of industrial activity and
contemporary life. Services now represent an undeniable force
behind labor and value creation in the world economy.

Until recent years, Tuttavia, design approached services as
if they were mere appendages to goods. It is not uncommon to still
observe in design discourse the surreptitious inclusion of services
in expressions like “product/service” or “product (and service),"
without a deeper explanation of the meaning of these compound
terms. By implication, the fixation on goods persists, che è
understandable considering design’s historical role in giving shape
to the material culture of modernity. But since the advent of post-in-
dustrial societies, the half-hearted integration of services into design
discourse is increasingly out of touch with the times. Services must
receive the attention they deserve so as to unpack the concept and
place it in the center of design thought and action.

Fortunately, there are signs within the design community of a
movement to advance service design.1 One of the issues motivating
current research is the idea that service designers create multiple
contacts, or touchpoints, between service organizations and their
clients, including material artifacts, environments, interpersonal
encounters, and more.2 The identification of touchpoints as an
object of service design is a clear step away from the imposition of
the goods-centered paradigms of the past. Tuttavia, touchpoints
remain poorly conceptualized from a design perspective. At best,
their origins in service research are traced back to the notion of service
evidence introduced in the seminal writings of G. Lynn Shostack in
marketing.3 Unfortunately, as we argue below, such a portrayal of
touchpoints places service design on the wrong track, because it
turns the design of services into a peripheral activity—namely, Quello
of “accessorizing” an essentially intangible relation between service
providers and their clients.

The lack of clarity over the object of service design is
aggravated by the superficial treatment in design scholarship of
the alternative concepts and theories found in the service literature.
In addition to Shostack, researchers from multiple backgrounds

1 Any attempt to provide an accurate

portrayal of a rapidly evolving field is
bound to suffer from incompleteness.
Ancora, as formative of the field of service
progetto, the following advances originat-
ing within the design community should
be mentioned. Articles published in
academic journals: per esempio., Nicola Morelli,
“Designing Product/Service Systems:
A Methodological Exploration," Progetto
Issues 18:3 (Estate 2002): 3–17; Carla
Cipolla and Ezio Manzini, “Relational
Services,” Knowledge, Tecnologia
& Policy 22:1 (2009): 45–50; Claudio
Pinhanez, “Services as Customer-
intensive Systems,"Problemi di progettazione
25:2 (Primavera 2009): 3–13. Specialized
research groups: per esempio., SEDES research,
led by Prof. Birgit Mager, at the Köln
International School of Design (Germany).
PhD theses of Pacenti, Sangiorgi, E
Cipolla, under guidance of Prof. Ezio
Manzini, at the Politecnico di Milano
(Italy). Networks bringing together prac-
titioners and academic institutions; per esempio.,
Service Design Network. Service design
consultancies; per esempio., live|work and Engine
(Great Britain). Dedicated conferences
in North America (Emergence 2007,
USA), Europe (Service Design Network
Conferenza 2008, The Netherlands), E
Asia (International Service Innovation
Design Conference 2008, South Korea).
Books and chapters in edited books:
per esempio., Gillian Hollins and Bill Hollins, Total
Design: Managing the Design Process
in the Service Sector (London: Pitman,
1991) and Bill Moggridge, Designing
Interactions (Cambridge, MA: MIT
Press, 2007). And other Internet-based
resources: per esempio., Jeff Howard’s “Design for
Service,” available from: http://progetto-
forservice.wordpress.com/ (avuto accesso
Giugno 19, 2010).

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have proposed conceptual handles for thinking about services in
the context of their development, commercialization, and use.
Tuttavia, their contributions are rarely recognized as relevant for
design and remain scattered across the literature, often obscured by
different disciplinary discourses. The purpose of this article is to
analyze these various service models in order to locate and ground
the object of service design in the broader field of academic research
on services.

Alternative Service Models
In this section, we introduce alternative service models discussed in
the literature from distinct disciplinary perspectives. Our exposition
is based on an extensive survey of academic publications on services
and is organized in four subsections, roughly corresponding to the
disciplines of service marketing, management, engineering, E
economics. The purpose is not to provide an exhaustive overview
of all the literature we consulted, but to focus on original contri-
butions that can impart knowledge about our topic of interest and
are widely applicable across service sectors. As such, there is a
certain bias in our selection toward older publications over recent
restatements of comparable ideas. Where appropriate, commentaries
about related work are added in side notes. We present each model
separately in an attempt to preserve their internal coherence and
conceptual integrity. Our descriptions thus remain observant of
the authors’ intentions and terminologies. Tuttavia, this approach
should not be taken to mean that we fully endorse each of these
service conceptions. Piuttosto, the goal is to explain relevant concepts
and theories in sufficient depth, and to invite readers to reflect upon
a number of received views of services and design. In doing so, we
highlight special features of the texts that are pivotal to the argumen-
tation developed in the section that follows, where we interpret the
content introduced and explicitly address the question of the object
of service design.

Shostack’s Evidence
In Breaking Free from Product Marketing, Shostack claimed that
marketing’s disregard for services could be attributed to an inability
to deal with their intangible nature.4 According to her, services
are impalpable and non-corporeal and, Perciò, “cannot be
touched, tried on for size, or displayed on a shelf.”5 The “dynamic,
subjective, and ephemeral” nature of intangible elements in services
prevents them from being described as precisely as products.6 The
introduction of her molecular modeling approach, illustrated in
Figura 1, was intended to provide a framework for dealing with
intangibility.

In a molecular model, goods and services may be represented
as combinations of discrete tangible or intangible elements, con
their identity being determined by the relative dominance of each

Design Issues: Volume 27, Numero 3 Estate 2011

Cf. Birgit Mager’s entry on service design
in Michael Erlhoff and Tim Marshall,
eds., Design Dictionary: Perspectives on
Design Terminology (Basel: Birkhäuser,
2008).

3 G. Lynn Shostack, “Breaking Free

4
5
6
7

from Product Marketing,"Giornale di
Marketing 41:2 (1977): 73–80.
Ibid.
Ibid., 75.
Ibid.
In the complete molecular model,
Shostack later included three outer
layers representing strategic marketing
decisions in terms of distribution,
price and cost, and advertising and
promotion. See G. Lynn Shostack, "Come
to Design a Service,” European Journal
of Marketing 16:1 (1982): 49–63. Along
similar lines, Booms and Bitner sought
to expand the traditional 4P marketing
framework (Prodotto, place, promotion,
and price), by incorporating three novel
elements (people, processi, and physical
ambiente) into an upgraded 7P
marketing mix for services. See Bernard
H. Booms and Mary J. Bitner, “Marketing
Strategies and Organization Structures
for Service Firms,” in Marketing of
Services, ed. James H. Donnelly and
William R. George (Chicago: American
Marketing Association, 1981), 47–51.
Also consider Lovelock and Wright’s
addition of an eighth “p” representing
service productivity and quality). Vedere
Christopher Lovelock and Lauren Wright,
Principles of Service Marketing and
Management (Upper Saddle River, NJ:
Prentice Hall, 1999).

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Automobile
(Prodotto)

Airline
(service)

Vehicle

Options
&
Extras

Service
Frequency

Transportation

Advertising

In-Flight
Service

Uniforms

Transportation

Pre/Post
flight services

Aircraft

Food and Drink

Figura 1 (above)
Molecular models describing cars (left)
and airlines (right). Circles represent intan-
gible elements; squares represent tangible
elements; dotted squares represent essential
evidence; and peripheral evidence is scattered
around the other elements.

9
10
11
12

Shostack, “Breaking Free from Product
Marketing," 77.
Shostack, “How to Design a Service," 53.
Ibid., 52.
Ibid., 51–2.
Ibid., 52.

type of element.7 Shostack argued that most goods and services lie
along a continuum from tangible-dominant to intangible-dominant.
In Figure 1, for instance, cars would be deemed products because
they are mainly physical objects with tangible options and extras;
even so, they also have a service dimension, as they incorporate
the intangible element of transportation, which may be marketed
independently. D'altra parte, airlines can be identified as
service providers because of the preponderance of intangible
elements.

Although intangible elements are the defining features of
services for marketers, Shostack also realized they do not represent
their total “reality” for consumers. She argued that because of the
abstractness of services, consumers cannot experience them directly,
but only through their peripheral tangible clues, or evidence. She
therefore defined service evidence as comprising everything “the
consumer can comprehend with his five senses.”8 In the airlines
example in Figure 1, this evidence includes the aircraft, advertising,
tickets, food and drinks, and other such items. Inoltre, staff often
stands as the main evidence of services because the way they dress
and speak, their hairstyles, demeanor, eccetera., “can have a material
impact on the consumer’s perception.”9 Because service evidence
is so important, Shostack believed that it “must be [COME] carefully
designed and managed as the service itself.”10

Shostack distinguished between two types of service
evidence: peripheral and essential.11 Peripheral evidence refers to
the tangible elements consumers can possess but that have little
independent value, such as tickets for airline services. In contrasto,
essential evidence, such as an aircraft, has an important role in
the evaluation of the services purchased but cannot be owned
by consumers. Although essential evidence was paramount in
Shostack’s conception of services, she considered such evidence to
represent “quasi-product elements”12 that could not have the status
of true tangible elements because, as such, they would have been
evidence of goods rather than services.

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Figura 2
Frame of reference for new service
development with service prerequisites
detailed.

13 The service blueprint initially was

presented in Shostack, “How to Design
a Service,” and later again in G. Lynn
Shostack, “Designing Services That
Deliver,” Harvard Business Review 62:1
(1984): 133–9.
Ibid., 138.

14
15 G. Lynn Shostack, “Service Positioning
through Structural Change,"Giornale di
Marketing 51:1 (1987): 34.

16 Shostack, “Designing Services That

Deliver," 136.

17 Several scholars later adopted service
evidence in their own service models.
Worth briefly mentioning are Berry and
Parasuraman’s identification of physical
ambiente, communications, and price
as crucial kinds of evidence, and Bitner’s
similar reference to people, processi, E
physical evidence. See Leonard L. Berry
e A. Parasuraman, Marketing Services:
Competing through Quality (New York:
The Free Press, 1991) and Mary Jo Bitner,
“Managing the Evidence of Service,"
in The Service Quality Handbook, ed.
Eberhard E. Scheuing and William F.
Christopher (New York: AMACOM,
1993), 358–70. More recently, the terms
“clues,” used by Pullman and Gross, E
“touchpoints,” by Zomerdijk and Voss,
were intended to convey Shostack’s
notion of evidence from an experience
design perspective. See Madeleine E.
Pullman and Michael A. Gross, “Ability
of Experience Design Elements to
Elicit Emotions and Loyalty Behaviors,"
Decision Sciences 35:3 (Estate 2004):
551–78 and Leonieke G. Zomerdijk and
Christopher A. Voss, “Service Design for
Experience-Centric Services,"Giornale di
Service Research 13:1 (Febbraio 2010):
67–82.

18 Bo Edvardsson and Jan Olsson, “Key

Concepts for New Service Development,"
The Service Industries Journal 16:2
(April 1996): 140–64.

Service Concept

Primary
Needs

Core
Services

ondary

N e eds S

orting S e r vices

Customer
Process

Customer
Outcome

Service
Prerequisites

Service Process

Act. 1

Act. 2

Act. 3

Service System

Organization &
Control

Clienti

Staff

Physical
Environment

Service evidence came to play an important role in Shostack’s
development of “service blueprinting,” a flowchart technique to aid
in systematic service design.13 In service blueprints, items of tangible
evidence usually become departure points for examining “hidden”
production activities that are internal to companies and beyond
direct customer contact, or in Shostack’s words, below their “line of
visibility.”14 Shostack’s work on service blueprinting, not presented
in detail here, ran alongside the growing focus of her thoughts on the
notion of process, which she eventually saw as the service equivalent
of a product’s “raw materials.”15 Nonetheless, even as her views on
the role of service design centered more and more on blueprinting
processes, Shostack maintained that companies should always
“incorporate the orchestration of tangible evidence.”16, 17

Edvardsson and Olsson’s Prerequisites
Edvardsson and Olsson’s service conception is an amalgam
of views commonly circulating in the broad area of service
management studies.18 These authors were concerned that the
quality shortcomings faced by many companies were “built into”
their services at an earlier design phase. In response, they sought
to develop a frame of reference for new service development that
would help companies to improve service quality by design.

According to Edvardsson and Olsson, the service construct
comprises three elements, as seen in the left side of Figure 2. Nel
first place, there is the service outcome, or what customers perceive
and value as the result of service production. Service outcomes can
be tangible or intangible, temporary or lasting. A haircut would be
a tangible, temporary outcome for customers, whereas an insurance
policy would represent an intangible and lasting outcome. Service
outcomes are formed by customer processes on the one hand and

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19 Other researchers have also regarded
higher levels of customer involvement
in production processes to be the most
important variable in characterizing
service operations and in setting strate-
gic directions for the design of service
systems. See R.B. Chase, “Where Does
the Customer Fit in a Service Operation?"
Harvard Business Review 56:6 (1978):
137–42; Urban Wemmerlöv, “A Taxonomy
for Service Processes and its Implications
for System Design,” International Journal
of Service Industry Management 1: 3
(1990): 20–40; Scott E. Sampson and
Craig M. Froehle, “Foundations and
Implications of a Proposed Unified
Services Theory,” Production and
Operations Management 15:2 (Estate
2006): 329–43; and Pinhanez, “Services
as Customer-intensive Systems.”
20 Edvardsson and Olsson, “Key Concepts
for New Service Development," 145.
Ibid., 147.

21
22 Elsewhere, Edvardsson named the

service process and system components
the servuction process and system,
rispettivamente. See Bo Edvardsson, "IL
Role of Service Design in Achieving
Quality,” in The Service Quality
Handbook, ed. Eberhard E. Scheuing
and William F. Christopher (New York:
AMACOM, 1995), 331–46. Servuction
is a neologism combining the words
“service” and “production” to denote
the simultaneity of production and
consumption in services. In line with the
original servuction system, customers
interact with the “visible” part of a
service organization, which consists
of the physical environment, contact
personnel, other customers, E
customers in person. See E. Langeard et
al., Services Marketing: New Insights
from Consumers and Managers, vol. 81
(Cambridge, MA: Marketing Science
Institute, 1981).

23 The service concept is a term commonly
encountered in the literature. Clark
et al. presented an elaboration of the
service concept in terms of value, form
and function, experience, and outcomes.
See Graham Clark, Robert Johnston,
and Michael Shulver, “Exploiting the
Service Concept for Service Design
and Development,” in New Service
Development: Creating Memorable
Experiences, ed. James A. Fitzsimmons
and Mona J. Fitzsimmons (Thousand
Oaks: Sage Publications, Inc, 1999),
71–91. See also Susan Meyer Goldstein
et al., “The Service Concept: The Missing
Link in Service Design Research?"
Journal of Operations Management 20:2
(April 2002): 121–34.

service prerequisites on the other. Customer processes refers to the
active participation of customers in production processes, Quale
Edvardsson and Olsson saw as a distinctive characteristic of services
as opposed to goods.19 Customer processes do not exist in a vacuum
but depend on the service prerequisites, which are the resources
needed to make the service possible. By engaging in production
processes, customers use service prerequisites and co-produce
outcomes for themselves. Edvardsson and Olsson thus argued
for understanding services from a customer perspective: “It is the
customer’s total perception of the outcome which ‘is the service’
… what the customer does not perceive does not exist—is not a
customer outcome.”20

If outcomes can represent the whole service for customers,
Edvardsson and Olsson held that prerequisites are closely associated
with the company perspective: “the service company does not
provide the service but the prerequisites for various services.”21
They organized new service development activities around the
three prerequisite components: service concept, service process,
and service system (Guarda la figura 2, right side).22 The service concept23
is a brief description of the service package24 (core and supporting
services) that answers different customer needs (primary and
secondary). It is the departure point for specifying all other prereq-
uisites. The service process represents the chain of activities necessary
for service production. Edvardsson and Olsson explained that the
service process is a prototype for the activation of customer processes
upon each unique customer encounter. Finalmente, the service system
comprises the resources the service process requires to realize the
service concept: company staff, customers, physical/technical
ambiente, and organization and control.25

It is at the level of service system resources that Edvardsson
and Olsson address service development activities in more detail.
They considered company staff to be a key resource because
many services depend on the tangible encounter between the
staff and customers. Companies should aim to have motivated,
knowledgeable, and committed staff, partly by devising attractive
jobs and hiring and training the staff properly. Secondo, customers
themselves could take part as prerequisites of the service system
by contributing their own knowledge, equipment, and capacity to
assimilate information. According to Edvardsson and Olsson, IL
service system should be designed to facilitate the engagement of
customers in co-producing the outcome. Marketing could also help
to establish relations between companies and their customers, for
instance, through the design of invoices and information materials.
The third resource, the physical/technical environment, pointed to
the organization of the facilities, equipment, and other technical
systems located on the service company’s own premises or those of
its suppliers and customers. Finalmente, organization and control involved
several activities: putting in place administrative systems to support

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Figura 3
Breakdown of an entire restaurant
service process.

24 The service package, sometimes called
bundle, or offering, is a multifaceted
concept. Lovelock proposed a basic sepa-
ration between core and supplementary
services, to which Lovelock and Wirtz
later added delivery processes. Vedere
Christopher H. Lovelock, “A Basic Toolkit
for Service Managers,” in Managing
Services: Marketing, Operations, E
Human Resources, ed. Christopher H.
Lovelock, 2nd ed. (Englewood Cliffs,
NJ: Prentice-Hall International, 1992),
17–30, and Christopher Lovelock and
Jochen Wirtz, Services Marketing:
People, Tecnologia, Strategy, 6th ed.
(Upper Saddle River, NJ: Pearson/
Prentice Hall, 2006), 22–5. Grönroos
departed from this conception of a basic
package and described an augmented
service offering. See Christian Grönroos,
Service Management and Marketing:
Managing the Moments of Truth in
Service Competition (Lexington, MA:
Lexington Books, 1990). In a second
line of thought, Sasser et al. E
Fitzsimmons and Sullivan defined the
package as comprising physical items
and facilities, sensual benefits (or explicit
services) , and psychological benefits (O
implicit services) . See W. Earl Sasser,
R. Paul Olsen, and D. Daryl Wyckoff,
Management of Service Operations:
Testo, Cases, and Readings (Boston:
Allyn and Bacon, 1978) and James A.
Fitzsimmons and R. S. Sullivan, Service
Operations Management (New York, NY:
McGraw-Hill, 1982). Normann further
synthesized these latter insights with
the previous separation between core
and supplementary services. See Richard
Normann, Service Management: Strategy
and Leadership in Service Business, 3rd
ed. (Chichester, NY: Wiley, 2001). IL
service package was also considered
in other hybrid conceptualizations,
such as Lehtinen’s service consumption
process and Grönroos’s service produc-
tion system. See J. R. Lehtinen, Quality
Oriented Services Marketing (Tampere,
FI: Tampereen Yliopisto, 1986) E
Grönroos, Service Management and
Marketing: Managing the Moments of
Truth in Service Competition.

Restaurant Services

Processes

Inputs

Outputs

Ordering

Customer Recieves
Menu

Meal is Delivered

Customer Service Activities

Service Operation Activites

Order is Delivered
to Kitchen

Order is Prepared
in Kitchen

Order is Collected
from Kitchen

Dining

Meal is Delivered

Customer Requests Bill

Billing

Customer Requests Bill

Payment is Collected

Leaving

Payment is Collected

Customer Departs

planning, information exchange, finance, and resource allocation.
Inoltre, the company’s interaction with customers and other
partners needed to be controlled by planning such aspects as how
to gather feedback and how to handle complaints. Inoltre, IL
company should also consider its organizational structure, con
proper definition of roles, responsibilities, and authority.

Ramaswamy’s Processes
Ramaswamy turned to the key notion of process, making it the
centerpiece of a comprehensive framework for the design and
management of services.26 His framework is so methodical and
formalized that it can be seen as a forerunner to several service
engineering approaches.27 From his elaborate work, we highlight
the stages where service processes are conceptualized and detailed
for implementation because these phases are particularly relevant
for design.

For Ramaswamy, services are fundamentally “nonphysical”
entities.28 A service process is a sequence of activities that provide
functions, chronologically organized as a unity. A process may be
further divided into smaller sub-processes and sub-subprocesses,
and is organized hierarchically, so that a higher level process is
completely assembled from its component sub-processes. Service
processes comprise two sorts of activities: service operations activities,
which reflect the steps needed by service providers to transform
inputs into outputs, and customer service activities, representing the
interactions between customers and service providers. An ideal
service process begins with input from customers and ends with
“visible” output for them.29

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Figura 4
Breakdown of the ordering process
of a restaurant service.

Restaurant Services

Subprocesses

Design Dimensions and Alternatives

Engineering Requirements

Menu reading and
ordering

Screen Display Format

1 item/page with detailed description

# of menu pages

# menu items

All items on 1 page with description on
help screen

menu display interval

page refreshment interval

appetizers, desserts, entrees, E
beverages on separate pages with brief
descriptions.

eccetera.

Availability Verification

Verification Procedure

for each item upon ordering

for all items after ordering

Accessing time

Inquiry time

Order Validation and
Correction

Verification Procedure

Waiter sends order to kitchen upon
receipt;corrections are sent later, after
validation

Transmission time

Maximum time for
validation

Waiter holds order until complete
validation;corrections before sending
order to kitchen

Figura 3 presents a sample breakdown of a restaurant
service process, beginning with the arrival of the guests and ending
when they leave the establishment. Note how the ordering process
(second row) consists of customer service activities, represented
by customers’ receipt of the menu and later their meals, anche
as service operations activities related to meal preparation in the
kitchen.

Ramaswamy claimed that the functions of a new service
process should be approached as problems guiding the design of
solutions. In his systematic framework, solutions for new processes
evolve from broad concepts, associated with larger processes, A
detailed components related to progressively smaller sub-processes.
Figura 4 illustrates three sub-processes of the ordering process:
menu reading and ordering, availability verification, and order
validation and correction. According to Ramaswamy, solutions for
the sub-processes may be devised by altering key design dimensions,
or the “characteristics that can be manipulated to influence the
performance of the design.”30 In his example of a computer-assisted
ordering process, these dimensions included the screen display
format, menu display, verification procedure, and validation method
(middle column).

Specifying design dimensions in different ways results in
various solution alternatives, as enumerated below each design

Design Issues: Volume 27, Numero 3 Estate 2011

25 Service culture was later added by

Edvardsson et al. as a fifth component of
the service system. See Bo Edvardsson
et al., New Service Development and
Innovation in the New Economy (Lund,
Sweden: Studentlitteratur, 2000). Another
version of the service system briefly
contemplated some external influencing
factors. See Bo Edvardsson, “Quality in
New Service Development: Key Concepts
and a Frame of Reference,” International
Journal of Production Economics 52:1
(ottobre 1997): 31–46.

26 Rohit Ramaswamy, Design and

Management of Service Processes:
Keeping Customers for Life (Reading,
MA: Addison-Wesley, 1996).

27 Although notable differences hold true,
other researchers also took process,
or activity, as the main building block
of their service models, often drawing
on knowledge from such areas as
mechanical engineering, systems
engineering, and computer science, E
progressing toward more consistent
notation, mathematical formalization,
and computational modeling. Vedere, for
esempio, Qinhai Ma, Mitchell M. Tseng,
and Benjamin Yen, “A Generic Model
and Design Representation Technique
of Service Products,” Technovation 22:1
(Gennaio 2002): 15–39; T. Arai and Y.
Shimomura, “Proposal of Service CAD
System: A Tool for Service Engineering,"
CIRP Annals—Manufacturing Technology
53:1 (2004): 397–400; Robin G. Qiu,
“Computational Thinking of Service
Sistemi: Dynamics and Adaptiveness
Modeling,” Service Science 1:1
(Primavera 2009): 42–55.

28 Ramaswamy, Design and Management

of Service Processes: Keeping Customers
for Life, 13.
Ibid., 128.
Ibid., 173.

29
30

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Figura 5
Characteristics model of services.

C1, C2, C3, …Cq)
Competence
Characteristics

C’1, C’2, C’3, …C’q)
Competence
Characteristics

Y’1, Y’2, Y’3, …Y’q)
Service
Characteristics

X1, X2, X3, …Xq)
Technical
Characteristics

dimension in Figure 4. Tuttavia, for Ramaswamy the configuration
of a new service process should be finalized only after iterative cycles
of evaluation and refinement of solution alternatives. As a result of
the final, most detailed design step, one optimal process solution
is specified in terms of the engineering elements (right column)
needed to create the process, including “the response requirements
of hardware, the look of a menu or screen, the contents of a script
to be followed by an employee, or the dimensions and weights of
parts.”31 This information, according to Ramaswamy, “is used by the
implementation team members who are responsible for constructing
the service.”32 In other words, engineering elements guide the actual
deployment of the new service process—“so far… a set of decisions
on paper”33—into a working service.34

Gallouj and Weinstein’s Characteristics
This final sub-section covers a service model from the field of
economics—more precisely, the work of Gallouj and Weinstein.35
Noting how extant research overly privileged the manufacturing of
goods, these authors sought to develop foundations for the analysis
of innovation activity in the service sector. Their approach begins
with the idea that a service seldom exists autonomously. The authors
see in this departure point an important difference from a good,
which upon production typically assumes a physical independence
from its producers and consumers: “[A service] is intangible and
does not have the same exteriority [of a good]… it is identical in
substance with those who produce it and with those who consume
it.”36 For them, this condition underlies many of the peculiarities
commonly associated with the production of services, such as the
necessary cooperation between providers and clients, the difficulty
in standardizing something dynamic and multifaceted, and the
confusion between product (“what” is delivered) and process (“how”
it is delivered). Gallouj and Weinstein’s formal representation of
services in terms of characteristic sets is shown in Figure 5.

Gallouj and Weinstein’s characteristics model consists of four
interacting sets. Set [Y], on the right, represents the service charac-
teristics. These are characteristics of services as seen from the user’s
point of view—in other words, the utilities provided by services to
clients. Examples include the user-friendliness and the deposit and
withdrawal functionalities of an automated teller machine. Set [X]

Design Issues: Volume 27, Numero 3 Estate 2011

Ibid., 251.
Ibid.
Ibid., 258.

31
32
33
34 Kaner and Karni also conceptualized
services as hierarchical systems
ultimately defined by the values given
to their lowest-layer components. Their
capstone model is a comprehensive,
five-tiered service representation,
consisting of 9 major classes (including
processi), 75 main classes, 351 minor
classes, and potentially thousands of
attributes and values. See Maya Kaner
and Reuven Karni, “Design of Service
Systems Using a Knowledge-Based
Approach,” Knowledge and Process
Management 14:4 (2007): 260–74.
35 Faïz Gallouj and Olivier Weinstein,

“Innovation in Services,” Research Policy
26 (1997): 537–56.
Ibid., 540.

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represents the technical characteristics that supply service charac-
teristics, which can be divided into tangible technical characteristics
(per esempio., information technologies, logistic technologies, chemical
products in cleaning services, eccetera.) and intangible technical charac-
teristics (per esempio., financial models, business execution methods, eccetera.).
According to Gallouj and Weinstein, technical characteristics can also
be divided into product and process characteristics by referring to
the interface between providers and clients. Così, product technical
characteristics would refer to “front-office” production activities
in close proximity to customers, while process technical character-
istics would be the “back-office” activities that don’t entail direct
customer contact. Although the authors believed in the validity of
this distinction, in the end they assumed that both product (front-
office) and process (back-office) technical characteristics could be
tangible or intangible, and could all be bundled in the same set [X].37
Gallouj and Weinstein further added competence character-
istics as a way to separate technical characteristics from human
capabilities. Set [C], according to the authors, represents provider
knowledge and skills embodied in individuals (or clearly delimited
teams), which are not easily dissociable from the people themselves
and therefore cannot exist autonomously or become part of organi-
zational knowledge. To highlight co-production by clients as a major
feature of services, Gallouj and Weinstein added client competence
characteristics (set [C’]) to represent knowledge embodied in
clients.

The complete model provides an integrative rationale for
service production: Service (Y) characteristics are obtained by the
direct application of competence characteristics of providers (C)
and/or clients (C’), in combination with mobilized technical (X)
characteristics {[C], [C’], [X], [Y]}. The model also takes account of
a particular class of “pure” services, such as consulting or massage
therapy services. In such cases, providers and clients co-produce
service characteristics without the involvement of any technical
means {[C], [C’], [Y]}.38 Tuttavia, Gallouj later observed that the
use of even unsophisticated technologies (per esempio., a towel for the
massage therapist) could represent an intervention of technical
characteristics.39

Based on the characteristics model, Gallouj and Weinstein
operationalized service innovation as “any change affecting one or
more terms of one or more vectors of characteristics (of whatever
kind—technical, service, or competence).”40 The authors further
noted that innovative changes might “emerge” as a result of “natural
learning mechanisms,” but they might also be “programmed,” or
“intentional, the product of R&D, progetto, and innovation activity.”41
Unfortunately, they did not explain how intentional innovation
could be attained specifically through the manipulation of charac-
teristics sets.42

37 Gallouj also briefly considered the inclu-
sion into the same set of spatial and
geographical organization character-
istics (per esempio., restaurant décor, proximity
of service establishment, eccetera.). Vedere
Faiz Gallouj, Innovation in the Service
Economy: The New Wealth of Nations
(Cheltenham: Edward Elgar Publishing,
2002), 53.
Based on the model, the authors
were also able to describe self-service
situations, where service character-
istics are created through the client’s
engagement with technical character-
istics alone, without the participation of
the provider competence characteristics
{[C’], [X], [Y]}. In another publication,
Gallouj also identified “pure goods”
situations, where there is no involvement
of competences embodied in humans
{[X], [Y]}. See Ibid., 59.
Ibid., 56.

39
40 Gallouj and Weinstein, “Innovation in

Services," 547.
Ibid.

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Locating the Object of Service Design
Having introduced representative service models in the extant
literature, in this section we articulate a conceptual framework
for locating the object of service design. Whereas previously we
described each model individually, now we adopt an interpretive
stance that engages with that same material. Our conclusion builds
up progressively in the following subsections.

Exchange Relations
One of the most fundamental aspects of service production is the
intertwining of stakeholders—most notably, providers and clients—
in exchange relations. As Gallouj and Weinstein noted, services are
not easily set apart from providers and clients as an independent
entity; they seem to exist to a substantial degree within this
context of economic exchange. Edvardsson and Olsson, as well as
Ramaswamy, also point out the necessary involvement of customers
in service co-production. Even when left implicit, as in the case of
Shostack, exchange relations are presumed based on the recurrent
references to both marketers and consumers.

Exchange relations establish the context for attributing
particular roles to the stakeholders involved in service
co-production. Typically, providers devise and market services;
clients purchase and use them. Inoltre, an investigation of the
circumstances of exchange relations reveals a host of sociotechnical
resources that are required for service production. For Gallouj and
Weinstein, service innovation could be linked to changes in terms of
human competences, plus tangible and intangible technical charac-
teristics. Other authors who were more prescriptive about service
innovation developed ideas about the planning and organization
of these resources. Following Edvardsson and Olsson’s framework
for new service development, companies should develop the right
prerequisites, which can then be processed by customers, leading to
high-quality outcomes for them. Allo stesso modo, for Ramaswamy, service
providers should engineer new production processes, whereas
customers should provide inputs and evaluate the outputs of such
processes. Finalmente, Shostack advises marketers to carefully manage
all the tangible evidence that can affect the consumer’s experience of
a service. In principle, Poi, design in services can be related to the
coordination of a varied set of sociotechnical resources, leading to
innovative forms of exchange between providers and clients.

Interface Versus Infrastructure
An analytical distinction introduced by many researchers is to
separate service production activities into two domains: IL
interface, which focuses on the sociotechnical resources immediately
associated with exchanges between providers and clients, and the
infrastructure, which accounts for resources less directly related
to that exchange. One criterion for distinguishing these domains

Design Issues: Volume 27, Numero 3 Estate 2011

In recent years, other authors have elabo-
rated on the characteristics approach
to service innovation. De Vries noted
how Gallouj & Weinstein’s model falls
short when representing innovation in a
network of organizations, where clients
co-produce a service by using their own
technologies. He reformulated both
the technical and competence charac-
teristics sets to account for multiple
organizations, and added the novel
client technical characteristics set. Vedere
Erik J. de Vries, “Innovation in Services
in Networks of Organizations and in
the Distribution of Services,” Research
Policy 35:7 (settembre 2006): 1037–51.
Windrum and García-Goñi, writing in the
context of health care, also pointed to
the need for representing innovation in
a multi-agent environment, and included
policy-makers as new stakeholders
alongside providers and users. They
further diminished the importance of
technical characteristics, proposing
instead that innovation in knowledge-
intensive services is better captured as
the negotiation over competence and
(newly-added) preference characteristics,
which are possessed by all agents. Vedere
Paul Windrum and Manuel García-Goñi,
“A Neo-Schumpeterian Model of Health
Services Innovation,” Research Policy
37:4 (May 2008): 649–72.

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suggested in the literature is their dislocation in time and space.
This is apparent in Ramaswamy’s restaurant example, where meals
are first ordered from and later served by waiters (the interface
comprises the customer service activities), while between ordering
and serving, the meals are prepared in the kitchen, out of the sight
of the customer (the infrastructure comprises the service operation
activities). A slightly different criterion was proposed by Shostack,
who introduced the concept of the line of visibility. This line
separates what is tangibly evident to the bodily senses of consumers
(interface) from what is hidden from them in the form of intangible
elements or processes (infrastructure). Inoltre, Gallouj and
Weinstein allude to a possible distinction between “what” results
for clients from product characteristics in the front office (interface)
and “how” this results from process characteristics in the back office
(infrastructure).

The interface and the infrastructure are inextricable
counterparts of the sociotechnical resources involved in exchange
relations, and both can be considered a concern for service design.
In Edvardsson and Olsson’s account, the company should plan the
interactions between customers, staff, and physical environments
for the exact moment of service co-production. But they should also
consider other necessary prerequisites, including those that must be
in place months before service provision begins (per esempio., administrative
systems for the allocation of financial resources).

A characteristic of the interface that merits attention, but that
has not been sufficiently stressed in the literature, is the particular
way in which the interface actualizes the co-production of the service,
as it conveys the infrastructure and brings to fruition the exchange
relation between providers and clients. Continuing the previous
esempio, for Edvardsson and Olsson the development of prereq-
uisites extends to infrastructure resources, but the goal is to influence
customers’ perception of the services. And this perception is created
at the interface, when the customers process the prerequisites into
outcomes. Also, for Ramaswamy the design of new service processes
includes the infrastructure, yet results in a working service for
providers only after implementation, when inputs and outputs
are actually exchanged with customers in service activities at the
interface. The relevance of the interface is acknowledged by Shostack
when she observes that service reality, at least for consumers, could
only be known through the tangible evidence. In sum, exchange
relations between providers and clients require the mobilization
of infrastructure resources but, ultimately, are realized through the
interface. For this reason, the interface becomes subtly prominent as
the end-point of all service design deliberations.

Materiality
In this subsection, we conclude our investigation by highlighting
the materiality of the service interface. Despite the emphasis on

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intangibility encountered throughout the service literature, many
researchers have commented on certain tangible aspects of the
service interface as well. Per esempio, Shostack deems services
inherently abstract and founded on processes. But she observes
that they could only be experienced by consumers through what
marketers make tangible to them. Ramaswamy, pure, places as
building blocks in his framework nonphysical processes, but he
later elaborates on them in terms of concrete engineering elements,
such as screen displays and other hardware in his restaurant service.
Gallouj and Weinstein also include tangible technical characteristics
in their characteristics sets. And for Edvardsson and Olsson, IL
physical/technical environment constitutes an important element
of the service prerequisites processed by customers.

That the service interface includes material artifacts and
systems can hardly be disputed. Allo stesso tempo, one of the
strongest convictions of researchers has been that services are
something more than—or, Infatti, anything but—a simple physical
“thing.” Can it be concluded that the service interface, in essence or
for the most part, is immaterial?

A closer look at the literature shows several types of
sociotechnical resources in services that differ from the material
artifacts identified. Per esempio, in their prerequisite list, Edvardsson
and Olsson include organization and control resources related to
organizational structure, administrative systems, and marketing
management. These resources are similar to Gallouj and Weinstein’s
intangible technical characteristics, which include financial expertise,
mathematical instruments, economic models, and so forth. Under
scrutiny, such resources seem to be located within the infrastructure
domain of the service provider. Therefore, as stated, these resources
need to be actualized through the service interface to affect exchange
relations with clients. Hence, Gallouj and Weinstein’s proposal that
services may be delivered by intangible technical characteristics
located at the front office appears to be unsubstantiated. The reason
is that, at the moment clients would encounter intangible technical
characteristics (per esempio., in the form of mathematical instruments
in consultancy services), they would experience them through
tangible manifestations (per esempio., slide projections, or words and graphs
in a printed report). The point, Ovviamente, is not to downplay the
importance of intangible technical characteristics, nor to reduce
them entirely to their tangible depictions. Invece, we suggest
Quello, for the production of services, intangible resources must be
actualized through an interface that is material and available to
bodily perception.

A problem area for the idea of a material interface is the
consideration of humans as sociotechnical resources, particolarmente
where providers and clients meet face to face. As Gallouj and
Weinstein observe, in the production of “pure” services, providers
and clients interact directly via skills and knowledge that might

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not be easily dissociated from them. One usual way of thinking
about the organization of interpersonal encounters in services
is to conceptualize human resources as abstract and inherent to
individuals. For Edvardsson and Olsson, Per esempio, company
staff members contribute to service production through their
knowledge, motivation, and commitment, which providers
could develop through proper recruitment and training, among
other indirect ways of influencing behavior. Another way of dealing
with person-to-person interaction has been to pinpoint human
resources of a more concrete but extrinsic nature. Per esempio,
Shostack observes that some manageable service evidences could be
found in the way contact employees dress, what they say, and their
hairstyles. Comparably, Ramaswamy includes in the engineering
requirements of new service processes the scripts that direct the
behaviors of people.

Interpersonal service encounters cannot be removed from
human subjectivity and spontaneity. Tuttavia, this reality does not
preclude personal interactions in services from being shaped, In
the absence of other material means, by the embodied behaviors
of providers and clients (per esempio., gestures, uttered words). What is
implied here is neither a simple “objectification” of human partici-
pation in service production, nor an argument for manipulating such
participation in the same way one would deal with other material
artifacts. Invece, our contention is that service exchange relations
between providers and clients are grounded on the materiality of
their interfaces, even in the case of interpersonal encounters.

For design, the crux of the matter might lie not in acknowl-
edging the materiality of the service interface, but in understanding
its distinctive nature. From our literature review, it appears that
every time empirical cases are used to exemplify what goods and
services are, researchers readily associate goods with a physical
thing, yet they fail to apply an equally concrete standard to services.
Di conseguenza, services are deemed intangible (or elusive, dynamic,
multifaceted, eccetera.), not because they are unavailable to embodied
experience, but because what their interface conveys is predominantly
not a standalone artifact with clear object boundaries. Invece, service
interfaces seem primarily related to embodied human interactions,
such as in Gallouj and Weinstein’s massage therapy service; diffuse
phenomena appealing to the senses, such as the tastes, smells,
and sounds in Ramaswamy’s restaurant service; multiple tangible
elements organized over time and space, as in Shostack’s airlines;
and possibly more. The distinctive characteristic that stands out in
these cases is not intangibility, but the material heterogeneity of the
service interface.

Our view sits close to Shostack’s concept of tangible evidence.
Tuttavia, Shostack believed that the true nature of services was
founded on intangible elements and abstract processes. Although
evidence was important for her, it represented in her view only a

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surrogate “reality” for consumers. Because Shostack reserves the
possibility of a genuine material existence for tangible elements,
which she associates with goods, she describes service evidence with
the derogatory term “quasi-products.” Service evidence thus came to
be inauthentic, peripheral clues of an intangible core. The implication
of this view, accentuated later when Shostack adopted processes as
the foundation of services, is that the design of evidence could now
represent just an ancillary activity, one that creates “accessories”
for immaterial services. We go beyond this view and claim that the
service interface materializes an exchange relation between providers
and clients, and that the design of the service interface, perhaps more
than anything else, is the design of the service itself.

A Pathway for Service Design
Shostack wrote three decades ago,43 and her work continues to
inspire researchers who seek to break free from goods-oriented
paradigms by stating that services are essentially intangible. Today,
this idea gains credence in the way that touchpoints are identified
as a central object of service design. The danger resides in defining
a touchpoint as a tangible interface between providers and clients
that is peripheral to an intangible service core. In stark contrast, we
claim that the client-provider interface is crucial to service design
because, ultimately, it brings new services into being. Inoltre,
by highlighting the material heterogeneity of such an interface, we
present a way for letting services be on their own, neither equating
them with the kind of artifacts associated with goods, nor abstracting
them into processes, nor resorting to their socioeconomic circum-
stances of co-production for a final explanation. Therefore, our
initiative to find a suitable object for service design, as much as it
is an effort to catch up with other disciplines, is also an attempt to
further our general understanding of services in ways that favor a
“designerly” approach to the matter.

We observe a clear tendency in the literature to develop more
elaborate analyses about the design of the service infrastructures
than of the interfaces. The rare discussions on service interface design
seem to arise as tangential, after-the-fact implications of planning
the infrastructure. This neglect of the interface coincides with the
embedding of design discussions primarily in service management
and engineering discourses, but also with the timid participation
in service research of design disciplines traditionally devoted
to phenomena in the interface domain of services (per esempio., Prodotto
progetto, interaction design, graphic design, and many others). Closer
attention to the interface would therefore appear to be a natural way
for these disciplines to take up new grounds in service research and
promote a deeper appreciation of design in services.

43 Shostack, “Breaking Free from Product

Marketing.”

Design Issues: Volume 27, Numero 3 Estate 2011

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Ringraziamenti
The authors sincerely thank Gui Bonsiepe, Petra Badke-Schaub,
Pieter Desmet, and Vera Blazevic for providing comments on an
earlier version of this article.

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Design Issues: Volume 27, Numero 3 Estate 2011
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