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A review of modeling approaches for sustainable supply chain management
Stefan Seuring
Supply Chain Management, Faculty of Business and Economics, University of Kassel, 34117 Kassel, Germany
a b s t r a c ta r t i c l e i n f o
Available online 3 June 2012
Keywords:
Supply chain management
Sustainability management
Quantitative modeling
Literature review
Environmental and social standards
More than 300 papers have been published in the last 15 years on the topic of green or sustainable (forward)
supply chains. Looking at the research methodologies employed, only 36 papers apply quantitative models.
This is in contrast to, for example, the neighboring eld of reverse or closed-loop supply chains where several
reviews on respective quantitative models have already been provided. The paper summarizes research onquantitative models for forward supply chains and thereby contributes to the further substantiation of the
eld. While different kinds of models are applied, it is evident that the social side of sustainability is not
taken into account. On the environmental side, life-cycle assessment based approaches and impact criteria
clearly dominate. On the modeling side there are three dominant approaches: equilibrium models, multi-
criteria decision making and analytical hierarchy process. There has been only limited empirical research
so far. The paper ends with suggestions for future research.
© 2012 Elsevier B.V. All rights reserved.
1. Introduction
Globalization places demands on supply chain management to
reach beyond pure economic issues and matters like e.g. fair laborconditions and environmentally friendly production. This raises inter-
est in its intersection with sustainable development, which is usually
comprehended in an economic, an environmental and a social dimen-
sion (see e.g. [45]; for the link to supply chain management see [70];
[42]). Managing supply chains in a sustainable mannerhas become an
increasing concern for companies of all sizes and across a wide range
of industries. Meeting environmental and social standards along all
stages of the supply chain ensures that (at least) minimum sustain-
ability performance is reached. This more reactive approach of
responding to external pressure from governments, consumers and
non-governmental organizations (NGOs) [71] and media can be com-
plemented by the development and introduction of sustainable
products.
For the period 1990 to 2007 Seuring and Müller [70] reviewed a
total of 191 papers. Toward the end of 2010 this list has grown to
about 308 related papers which published about green and sustain-
able supply chain management. Yet, sorting these papers according
to the research methodology employed, only 36 remain which build
or use quantitative models. Hence, this paper aims at taking a longer
period into account than Seuring and Müller [70], but focuses on one
kind of research method, i.e. quantitative models, only. This allows
detailed insights into this stream of research and should reach con-
clusions on how to develop it further. This small number and share
of models is in clear contrast to, for example, the neighboring eld
of reverse or closed-loop supply chains, where Fleischmann et al.
[46] already provided a rst review on “quantitative models for re-
verse logistics”
. Furthermore, (wider) literature reviews on relatedeldsare available:(1) closed-loop supply chains[50]; (2) green supply
chains, but alsowith a focus on reverse logistics [73] and (3) sustainable
supply chain management [70]. Recently, further reviews have been
published, which address particular topics. Two examples are those
on sustainable supply chain management and inter-organizational re-
sources [48] or those relating it to a wider set of constructs in supply
chain management [49]. Mollenkopf et al. [61] have emphasized the
link to lean management and globalization issues in their review. Carter
and Easton [42] evaluate particularly related empirical research,
restricting themselves to a set of papers taken from seven journals
mainly in the domain of logistics and supply chain management. Yet,
such a review has not been attempted for quantitative models applied
to the forward supply chain.
The aim of this paper is to summarize existing research on quanti-
tative models for forward supply chains, thereby aiming at substan-
tive justication as an important step in theory building [58]. This
provides insights toward future research directions and needs.
The paper is structured as follows: as the study deals with a liter-
ature review, a classical section labeled as such is not provided. In-
stead, the paper starts by outlining the content analysis method as
applied in the research process. Next, some descriptive background
on the papers (e.g. years of publication, major journals) is presented.
Further, the ndings from the content analysis are discussed, with a
particular focus on the sustainability dimensions and modeling ap-
proaches. This will lead over to the discussion of the ndings and
brief conclusions.
Decision Support Systems 54 (2013) 1513–1520
E-mail address: [email protected].
URL:http://www.uni-kassel.de/go/scm.
0167-9236/$ – see front matter © 2012 Elsevier B.V. All rights reserved.
doi:10.1016/j.dss.2012.05.053
Contents lists available at SciVerse ScienceDirect
Decision Support Systems
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / d s s
http://dx.doi.org/10.1016/j.dss.2012.05.053http://dx.doi.org/10.1016/j.dss.2012.05.053http://dx.doi.org/10.1016/j.dss.2012.05.053mailto:[email protected]://www.uni-kassel.de/go/scmhttp://dx.doi.org/10.1016/j.dss.2012.05.053http://www.sciencedirect.com/science/journal/01679236http://www.sciencedirect.com/science/journal/01679236http://dx.doi.org/10.1016/j.dss.2012.05.053http://www.uni-kassel.de/go/scmmailto:[email protected]://dx.doi.org/10.1016/j.dss.2012.05.053
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2. Describing the method and base for the literature review
This study forms part of a wider literature review at the intersec-
tion of sustainability and supply chain management. The methodolo-
gy applied has already been described in detail [70]. Papers were
identied by means of a structured keyword search on major data-
bases and publisher websites (Ebsco, Springerlink, Wiley Inter-
science, Elsevier ScienceDirect, Emerald Insight). Keywords such as“purchasing”, “sourcing”, “supply” and “supply chain”, and “logistics/
logistical” were combined with sustainability related ones, such as
“sustainable/sustainability ”, “sustainable development”, “environ-
ment(al)”, “green”, “social” and “ethics/ethical”. Subsequently, pa-
pers were screened in detail in a two-step process. First, there were
three issues excluded from further analysis: (1) reverse logistics
and remanufacturing, as they have already been subject to self-
contained literature reviews already [46,50], (2) ethical behavior of
purchasing staff, and (3) public procurement. Second, the papers were
unanimously assigned to one research method, where ve categories
were applied: modeling (the one used here), theoretical or conceptual,
case study, survey or literature review.
A content analysis was conducted to systematically assess the pa-pers [55,56,63]. Material collection has already been described by
means of the literature search and reduction mode. For the analysis
itself, a set of criteria is used at rst for describing the sample. Then,
the discussion is taken into the content analysis itself, where a mix-
ture of deductive and inductive as well as quantitative and qualitative
criteria is chosen. Respective criteria applied for the content analysis
are outlined below.
2.1. Basic terminology
2.1.1. Sustainable supply chain management (SSCM)
The denition of Seuring and Müller [70] who take standard de-
nitions of supply chain management [59] serves as a starting point:
“Sustainable SCM is the management of material, information andcapital ows as well as cooperation among companies along the sup-
ply chain while integrating goals from all three dimensions of sustain-
able development, i.e., economic, environmental and social, which are
derived from customer and stakeholder requirements. In sustainable
supply chains, environmental and social criteria need to be fullled
by the members to remain within the supply chain, while it is
expected that competitiveness would be maintained through meet-
ing customer needs and related economic criteria.”
2.1.2. Quantitative modeling
According to Bertrand and Fransoo [39] this is “model-based
quantitative research, i.e. research where models of causal relation-
ships between control variables and performance variables are devel-
oped, analyzed and tested”
. Such research methods are frequently
used in supply chain management research (see e.g. [38,60,57]). Sub-
sequently, four different quantitative approaches are distinguished,
which are briey introduced, while the full justication for using
them as categories is provided later in the paper.
2.2. Sample and descriptive analysis
The overall sample contains 309 papers in total (status papers
published up to the end of 2010). Out of this sample only 36 papersapply quantitative models, thereby only contributing little more
than 12% of the total number of papers.
Fig. 1 highlights the timely distribution of the 36 papers. Only two
papers were published before the year 2002 [29,31,6,7,24]. There is a
small peak in 2005 with seven papers, but this seems just accidental
as there was no special issue which would easily explain it. In current
years, there is an almost stable output with four or ve papers pub-
lished for each year in 2007–10 (see Fig. 1).
Regarding journals, where such papers appear most often, Journal
of Cleaner Production (JCLEPRO) is the leading journal with nine pa-
pers (or 24%) published. Four papers appeared in the European
Journal of Operational Research (EJOR), and three each in the Interna-
tional Journal of Production Economics (IJPE) and the International
Journal of Production Research (IJPR), in total contributing another27% of the sample. The rest of the papers are distributed across a
range of other journals.
2.3. Criteria applied in the content analysis
Establishing criteria for content analysis can be based on a deduc-
tive or an inductive approach. Here, the criteria are mainly derived
deductively and are based on the already mentioned literature re-
views in the eld (particularly [70] criteria). Yet, this would not be
suf cient for addressing all relevant issues, so in some cases, criteria
can only be established while working with the material. This was
the case here for the assessment of the modeling approaches applied
in the paper.
The following dimensions will be discussed, briey explained and
justied:
• First, the environmental, social and economic criteria or perfor-
mance objectives are assessed. In a second step, the integration of
environmental and/or social issues with economic objectives is an-
alyzed. This is in line with the typical three dimensional compre-
hension of sustainability (see e.g. [45]) and has been discussed in
the eld of supply chain management before (see e.g. [71,42]).
• The modeling approach taken in the paper is described. As there
was no clear starting point for this analysis, the categories were de-
rived inductively. Three categories, i.e. life-cycle assessment
models, equilibrium models and analytical hierarchy process, were
used right at the start, while the other two only appeared during
the coding.• The link to empirical data forms the nal dimension of the analysis
[42,69]. This allows insights into the eld research done toward ll-
ing the models with empirical data.
The ndings from applying these dimensions are now presented.
3. Analysis of the papers
In the following sections, the different dimensions of the analysis
will be presented. To allow easier presentation of the material, tables
will be used summarizing the single dimensions as embedded in the
papers. Unless stated otherwise, all gures refer to the sample of 36
papers analyzed here.
Fig. 1. Time distribution of the analyzed papers.
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3.1. Sustainability dimensions
Conceptualizing sustainability in three dimensions seems to be
widely accepted [45,42]. It allows an easy comprehension of the
integration of economic, environmental and social issues. This also of-
fers the justication of applying it in this paper. Hence, the papers are
categorized, based on how they relate to sustainable development. As
all papers are taken from management related literature, the eco-
nomic dimension forms an integral part and was therefore nottaken as a separate category. Yet, the papers show a very strong dom-
inance of addressing environmental issues (34 papers). There are no
papers that exclusively focus on social issues, and also integrating
all three dimensions of sustainability is only present in two of them
(i.e. [5,15]).
Seuring and Müller [70] emphasize the need for increasing coop-
eration along the supply chain, if sustainability goals are to be
reached (also [49]). Hence, this should be reected in related goals.
A closer look is therefore taken on each dimension and on which
goals are put forward.
3.1.1. Economic dimension
As only papers dealing with supply chain management are taken
into account, it is logical that economic issues are addressed. Most
often, total cost or net revenue is taken as indicators. Yet, there are
a number of papersnot providing insights into what kind of economic
goals is pursued. This holds for a rst set of papers that mainly follow
a life-cycle assessment (LCA) approach (e.g. [34]). Often, such papers
compare different alternatives toward their environmental perfor-
mance (e.g. [11,13]). In a number of cases, the current economic
situation is (inherently) seen as a kind of baseline for evaluating al-
ternatives on their environmental impact. This holds particularly for
the LCA related papers (e.g. [34,35,4,11]) or those applying AHP
[31,19,20,25,26].
3.1.2. Environmental dimension
Most papers spend much more effort on explaining related envi-
ronmental issues. In many cases, life-cycle assessment data forms
the starting point for the analysis. Hence, energy demand and CO2-emissions (e.g. [4,11,35,28]) are among the frequently mentioned
topics. Yet, in a number of cases, rather comprehensive lists of envi-
ronmental impact criteria are taken up, such as referring to all kinds
of natural capital (e.g. [36]) or resources, such as water or energy as
well as waste (e.g. [26,23,17]). Overall a wide range of environmental
aspects is taken into account. A deeper look provides some critique to
the typical approach chosen. The relationship between the LCA-based
environmental impacts and their management in the supply chain
often points to supplier selection (e.g. [29,20,25]) and optimization
issues, such as transport to end customers [33,11]. Hence, LCA based
approaches seem to dominate here as they allow comprehending
and modeling product-related impacts (for a conceptual note see
[64]).
3.1.3. Social dimension
The social dimension is the one that is addressed the least often in
the papers. Building on a rather strict assessment, 34 of the 36 papers
do not mention it at all. In four cases one could even argue that the
term corporate social responsibility (CSR) is rather misused in the
title of the papers looking at their content [8–10,21]. While all carry
CSR in their title, they rather model environmental issues, but not so-
cial impact related ones. Cruz [8,9] as well as Cruz and Matsypura [10]
briey refer to risk associated with not having (enough) CSR. Hsueh
and Chang [21] use it as starting point for a discussion on prot
sharing.
Yet, turning to the denition of CSR (for an overview see [44]), it is
evident that this is about voluntary measures of companies, particu-
larly in the relation between business and society. Hence, CSR cannot
be subject to a simplistic comprehension of just a single factor put
into any kind of quantitative model. While this is a normative state-
ment, the ongoing debate on CSR supports such a statement (e.g. [47]).
This would basically leave all assumptions of supply chain management
unquestioned and rather support a marginally changed business as
usual, where sustainability is still subordinate to economic issues. Just as
one closely related example, Halldórsson et al. [52] pointed out that
such an assumption is insuf cient for addressing sustainability.
A much wider perspective is taken by a few other papers. Rathermacro-economic social aspects are put forward by Clift [5], Foran et
al. [15] and Ukidwe and Bakshi [36]. They cover employment and in-
come distribution, thereby pointing to the wide range of responsibil-
ities of companies.
3.1.4. Integration of the three dimensions
The integration of all the three dimensions plays a central role, but
is not often addressed so farin related research [70]. Previousndings
have rather conrmed that the social dimension needs much better
integration with the economic and environmental ones.
A second approach is taken by looking at the goal relations among
the three dimensions (see Table 1). It has to be noted rst that each
paper is assigned here to one category only, while Seuring and Müller
[70] assigned papers into more than one category, therefore having atotal of 234 entries for 191 papers. Comparing the gures, it can be
seen that trade-offs among the environmental and the economic di-
mensions are most often taken as a starting point for building the
models. This will be discussed subsequently, after the modeling tech-
niques have been introduced.
This analysis already pointsto a clear research gap regarding social
aspects as well as the overall integration of the three sustainability di-
mensions. While this will not be an easy or simple task, such research
is much needed and would also allow links of sustainable supply
chain management toward other emerging elds, such as the Base-
of-the-Pyramid debate (see e.g. [51,66]).
3.2. Modeling approaches
Looking at the models proposed, they can be grouped into four
categories (see Table 2). The four categories were not chosen deduc-
tively, but emerged inductively while trying to group them when
reading and analyzing the material: (1) life-cycle assessment based
models, (2) equilibrium models, (3) multi-criteria decision making
(MCDM), and (4), applications of the analytical hierarchy process
(AHP). The overall objective is usually a cost minimization effort,
where the entities that incur costs and the respective cost elements
are specied. Each approach and the typical elements pertained
therein will be briey presented.
It has to be mentioned that each paper is assigned to one category
only. The equilibrium models and the multi-objective decision mak-
ing (MCDM) models take somewhat similar starting points and both
aim at nding a balance between different (environmental and eco-nomic) performance criteria. As a further issue, there are three papers
applying simulation as their method [24,34,14,30]. Yet, they do so ei-
ther for providing insights into LCA cases [24,34] or for evaluating
Table 1
Goal relations among the three sustainability dimensions.
Goal relations Seuring and Müller [70]
(N=191 papers)
(N=234, multiple counting allowed)
Modeling papers
(N=36 papers)
Win–win-situations 124 (53%) 7 (19%)
Trade-offs 72 (31%) 20 (56%)
Minimum performance
for environmental
and social issue
37 (16%) 9 (25%)
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variables among a multi-objective decision making approach [14].
Hence, they are grouped into the respective categories.
Table 2 provides an outline of the different modeling approaches
used, briey describing the typical approach taken and listing the pa-
pers that were grouped into the respective category.
3.2.1. Life-cycle assessment (LCA) based studies
Life-cycle assessment is a product based on environmental assess-
ment techniques (e.g. [54]), which was even standardized in the ISO14041. It is rst discussed here, as it often forms a kind of background
for the other modeling approaches. LCA-type data is pointed to in 29
of the 36 papers. The papers mainly present life-cycle assessment
data and illustrate its use in a specic context or case application.
This is well in line with earlier analysis, such as the concept suggested
by Pesonen [64], who already pointed to the use of life-cycle
assessment based criteria in supply chains. Furthermore, Seuring
[67] elaborates that LCA-based criteria usually provide the product
optimization perspective which precedes the supply chain optimiza-
tion. In this respect, it is no surprise that LCA type data serves as a
background for subsequent optimization in the papers reviewed
here (e.g. [14,13]). The link to products is evident, as a core line of re-
lated research is labeled as supply chain management for sustainable
products (e.g. [70,69]).This also offers a link to the already discussed environmental di-
mension and related performance objectives (see Section 3.1). In
total, a broad range of environmental emissions and impacts is re-
ferred to, while related impact assessments usually concentrate on
the direct emission level.
One further typical element is the focus of a number of papers on
one product or industry, such as aluminum [24,35,13], milk [34], elec-
tronics [18] or services, particularly book distribution [11] or wine
distribution [4]. This allows reducing the environmental issues dealt
with as well as making respective supply chain related decisions
more evident. While the LCA-studies therefore often stay on general
supply chain wide aspects and in many cases do not center on a single
actor or actor network in the supply chain, such is usually the case in
the other approaches taken in respective papers.
3.2.2. Equilibrium models
The already mentioned line of research on assessing performance
of an overall supply chain or even industry is continued within the
papers aiming at indentifying an equilibrium. This is a standard
modeling technique [62] and is well established (e.g. [57]). Such equi-
librium would be established by assessing what the optimal level of
investment into environmental (abatement) technologies and re-
spective economic returns would be. Kainuma and Tawara [23] start
this debate by proposing a multiple utility function approach, whichbuilds on metrics in three dimensions: (1) LCA, (2) supply chain re-
turn on assets and (3) customer satisfaction. A starting point for relat-
ed research was presented with the shared savings contract model for
indirect material [7]. The environmental consideration is easy to com-
prehend as it aims at reducing the amount of indirect materials being
applied. Staying with environmental considerations but aiming at a
much wider equilibrium among natural and economic capitals,
Ukidwe and Bakshi [36] present their model, mainly building on ther-
modynamic input–output analysis. Nagurney and Toyasaki [27] for-
mulate a more specic model based on manufacturers, retailers and
consumers, but stay vague about what kind of emissions is actually
dealt with.
The above already criticized papers modeling CSR activities also
fall into this category. Hsueh and Chang [21] stay particularly vague
about what CSR would imply: “Herein, undertaking CSR is originally
utilized for coordinating the decentralized supply chain.” In the
model itself, this is only present in a production function as “per-
ceived production and inventory cost of manufacturer (considering
CSR)” [21]. Cruz [8] handles this in a similar manner, even claiming:
“We note that any level of social responsibility activities between any
two parties in the supply chain requires a strong level of collaboration/
cooperation between them.” Such an approach is made somewhatclear-
er in the paper by Cruz and Matsypura [10] who claim that “engagement
in CSRis assumed to reducetransactioncosts, waste,as well as risk.” This
is one of the assumptions forming the background for modeling a re-
spective network of manufacturers and retailers. In the equilibrium, an
optimal solution is found for CSR related investments, products' ows
along the supply chain and respective prices.
A similar approach is presented by Saint Jean [30], but is based onemission standards, which seems easier to comprehend. Here, the
minimum performance level of environmental and social standards
[70] is pointed to, which seems much more straightforward than
unspecied investments into CSR. This refers to the overall contribu-
tion of these models, which evaluate the consequences of introducing
some sort of minimum performance criteria. While the problem
statement and model formulation for environmental issues seem
straightforward, the integration of social issues needs further elabora-
tion and a clearer positioning whether minimum standards, e.g. for
working conditions and payment, are reached or whether voluntary
CSR activities are expected. It is emphasized again that these models
evaluate the overall equilibrium among a given set of market actors,
but do not directly aim at their decisions. Such focus is taken within
the other modeling approaches.
3.2.3. Multi-criteria decision making (MCDM)
The link to the previous category is evident, in e.g. the paper of
Sheu et al. [33], who use multi-objective programming but also assess
the equilibrium among manufacturing chain and reverse chain, in-
cluding e.g. transaction costs and recycling fees. This showcases the
typical idea of the papers where different objectives have to be met
at the same time, which makes the point for such multi-criteria deci-
sion making approaches (e.g. [60]). Hence, the focus is usually not so
much on reaching an equilibrium situation, but rather dealing with
trade-offs among conicting objectives. There is a somewhat weak
line among these papers looking more at single company/supply
chain based decisions and the previous category. An ef cient logistics'
network conguration is at the core of the arguments presented by
Table 2
Grouping papers according to modeling techniques.
Modeling approach Typical element of
the model
Related papers
Life-cycle assessment (LCA)
models (11 papers)
Assessing
environmental
impacts along a
supply chain and
minimizing them.
[3–6,11,13,15,18,24,34,35]
Equilibrium models (9papers)
Balancingenvironmental and
economic factors and
nding an
equilibrium or
optimal solution.
[7–10,21,23,27,30,36]
Multi-criteria decision
making (6 papers)
Optimization of
economic and
environmental
criteria, usually
balancing trade-offs
or identifying opti-
mal solutions.
[14,16,17,22,28,33]
Analytical hierarchy
process (8 papers)
Structuring a
decision process
thereby obtaining a
solution based on
semi-quantitativecriteria and respec-
tive weights.
[1,2,12,19,20,25,26,29,31,32]
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Neto et al. [28]. In line with the LCA studies and equilibrium models,
they mention that trade-offs would be based on societal decisions
based on Pareto ef ciency. Their model could help in making respec-
tive decisions and is clearly linked to the equilibrium models already
described. Hugo and Pistikopoulos [22] also use LCA data as their
starting point and integrate this into modeling the supply chain for“environmentally conscious strategic investment planning”.
More into detail are e.g. Fichtner et al. [14], assessing joint invest-
ments into inter-
rm energy supply and respective savings. Quitesimilarly, Geldermann et al. [16] look at a bicycle manufacturer in
China. Heat integration, water management and solvent recovery
are the environmental issues addressed and optimized. While these
two papers already point to supply chain design, this is emphasized
in the two papers remaining in this category.
3.2.4. Analytical hierarchy process (AHP)
The logic of LCA-data is also evident in the paper applying the
AHP, similar techniques or modications thereof. The AHP is also a
multi-objective decision making technique [65]. The major difference
is that it is not based on a full mathematical formulation of a certain
problem, but is called a semi-quantitative decision making technique
simplifying and structuring decisions (e.g. [65,53]). This justies an
own category, different from the two previous ones. The two paperspublished early in the entire data set are based on this semi-
quantitative decision technique [29,31]. The AHP allows evaluating
not only complex decision situations, where environmental and eco-
nomic goals are assessed at the same time (e.g. [31,32,19,12]), but
also more specialized decisions, such as looking at the role of
hazardous substance management [20] or green supplier selection
[29,26,25] and supplier development practices [1,2]. The last two pa-
pers somewhat form their own category as they apply rough set the-
ory. Yet, as this also deals with incomplete information and follows
similar aims as the AHP, it was decided to keep them in the same
category.
Overall, the decisions evaluated focus on improving environmental
performance toward greening respective products [41,70]. Compared
to the previous two categories, the aim is not so much reaching an equi-libriumor optimal approach but rather pointing toward the complexity
of decision making and emphasizing the inuence of the decision
makers. AHP allows taking different decision criteria into account and
evaluating them without necessarily connecting all of them into one
quantitative model. Hence, such an approach may also be called
multi-objective decision making (e.g. [26]), but building on managerial
judgments.
3.3. Interrelation of modeling approaches and goal relations
As a further step, it is interesting to combine the two analytic di-
mensions of goal relations and modeling approaches. As briey men-
tioned, the analytic dimensions and categories for the content
analysis are often derived inductively and are then validated againstthe interpretation and understanding they offer.
This kind of construct validity is derived from the two analytic di-
mensions, jointly offering interesting insights into how the typical
models look and thus allowing a distinction among them (discrimi-
nant validity). This is shown in Table 3.
The equilibrium models as well as the multi-objective decision
making build on trade-off situations among environmental and eco-
nomic goals. There is only one MCDM paper which takes its starting
point from a win–win situation [14]. This is also the only one building
on data from a practical environment.It almost seemsobvious that these models take their starting point
from trade-offs between the economic and environmental dimen-
sions. Such trade-offs are a critical aspect of sustainable supply
chain management and often form the starting point for respective
action [71]. Further, trade-offs are more straight forward to model
in these approaches.
All three goal relations are observed only for the LCA based papers.
This is in line with the previous nding that LCA data forms a back-
ground for many of the studies presented here. While the trade-offs
dominate, the two other categories are also found. Foran et al. [15]
as well as Tan and Khoo [35] take win–win-situations as their starting
point. Both apply an analysis of statistical data. The latter looks at
cleaner production and process improvements in the aluminum sup-
ply chain. Foran et al. [15] look at different products relevant for pri-
vate consumption (e.g. cotton and vegetables).
There are three papers arguing for minimum conditions for envi-
ronmental and social performance [34,3,18]. The paper by Sonesson
and Berlin [34] is based on the milk supply chain, while Brent ad-
dresses the automotive one. All papers have in common that they
rather argue on a macro-level, well in line with the win–win-category
ones. It seems to be more straightforward to depart from a trade-off
assumption if the level of analysis is not focused on just a single com-
pany and its respective supply chain.
For the AHP papers, there are contrasting ndings as there are no
papers dealing with trade-offs. While four look at win–win situations
[31,32,26,12], there are six taking environmental issues as minimum
standards against which economic decisions have then to be made
(see Table 2). The selection of the decision criteria is more exible
within the AHP as they are rather connected in a logical but not in amathematical matter. This allows choosing criteria that represent ei-
ther win–win-situations or minimum standards. The most recent de-
velopment in this category, namely being the application of rough set
theory [1,2], also allows evaluating performance issues of each com-
pany as well as the supply chain in total, an issue not addressed in
the previous publications in this category.
3.4. Illustrations and empirical data
Many modeling papers contain a theoretical example of numerical
illustration of the model presented (see Table 4). This is also found
here, as 28 papers in total do so. The purpose of such an illustration
usually emphasizes the consequences of the decision making for areal life application. Yet, very few papers actually build on empirical
research. On most occasions, the illustration is “made up”. Only one
paper is purely theoretical and does not contain any such information
[5]. Few examples are found to be different. Fichtner et al. [14] use an Table 3
Relationship among goal relations and modeling approaches.
Goal relations Modeling approach Sum
LCA
model
Equilibrium
model
Multi-criteria
decision
making
Analytical
hierarchy
process
Win–win situations 2 0 1 4 7
Trade-offs 6 9 5 0 20
Minimum performance
for environmental and
social issues
3 0 0 6 9
Sum 11 9 6 10 36
Table 4
Empirical research presented in the papers.
Empirical content No. of papers (N = 36)
Theoretical or numerical example 28 (all others not listed below)
Statistical data 5 [6,15,24,34,36]
Empirical data 2 [14,19]
None 1 [5]
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industrial network in the Karlsruhe area, Germany, as background for
their model, thereby relating to real world data. Others take industrial
sector data, such as the example of the European pulp and paper in-
dustry [28], but stay at an illustrative level. Such statistical data is
used most often in LCA-type studies, which make up four of the ve
papers offering such an approach [6,15,24,34]. Only Ukidwe and
Bakshi [36] build a thermodynamic input–output model on 488 sec-
tor data sets for the USA, thereby assessing an equilibrium situation
between natural and economic capitals (Table 4).Besides the already mentioned model based on real technical data
by Fichtner et al. [14], there is only one paper presenting empirical
data. A survey feeding into the decision making process is found in
Hsu and Hu [19], who take responses from 87 managers for validating
their AHP model.
Overall, it has to be concluded that the link to empirical data is
missing for most of the related research. Yet, combining the models
presented with empirical data should offer interesting insights and
hence provides a sound direction for future research.
4. Discussion
This paper provides a rst review of publications applying a
modeling approach for green or sustainable supply chain issues. Thecontribution of this review lies in aggregating the so far scattered
publications on this topic and providing an overview on the ap-
proaches taken therein.
4.1. Sustainability dimensions
Several conclusions can be drawn, which rst of all relate to the
three dimensions of sustainability:
• The social dimension is almost completely missing or sometimes
comprehended in a far too simplied manner. It might be dif cult
to model social impacts. This is in line with wider literature reviews
(e.g. [73,70,49]), which also found a lack of research on social as-
pects. Hence, there seems to be a challenge for the wider range of related research, while social aspects might have to be evaluated in
detail before they are suitably integrated in such (multi-objective)
modeling approaches.
• The environmental dimension is mainly treated by building on life-
cycle assessment-based categories. Yet, many papers stay vague
about the kind of environmental impacts taken into account.
Some specify the environmental impacts of a particular product or
supply chain process and mention how to deal with them. Such
models would offer the chance to look at particular impacts and
offer guidance to practitioners on how to deal with them. This
also points to a more theoretical stream of research, which assesses
the role of LCA-data in supply chain decisions. Here, a link to empir-
ical researchon the decision makers would be relevant in particular.
• In the economic dimension, “total” cost-based or decision relatedcost and revenue approaches dominate. This does not really capture
how proactive companies strive to implement green or sustainable
supply chains and thereby actively managing a number of perfor-
mance objectives. Some of the AHP related papers point to this
and thereby get closer to what Seuring [69] calls supply chain man-
agement for sustainable products. Widening the scope of economic
performance criteria would be a welcome contribution.
• Last but not least, the integration of the three dimensions as well as
the interrelations among sustainability dimensions and objectives
demand further research. Previous modeling research mainly
looks at trade-offs. While this might be a sound starting point for
decision making, the consequences of either win–win situations or
environmental and social standards as minimum criteria also war-
rant further research.
4.2. Limitations
The rst limitation of this paper comes from the small sample size
of only 36 papers. This has been justied as no previous literature re-
view or similar approach has been presented on quantitative model-
ing approaches in sustainable supply chain management. A second
limitation is that only a number of quantiable criteria are used for
the content analysis. Only meaning embedded into these categories
is extracted from the papers. Yet, it is obvious that each paper wasread more than once during the coding and thereby other aspects
came forward in a more inductive manner. The range of codes could
be expanded, so that e.g. the environmental dimension is analyzed
in more detail. Furthermore, the quantitative models could be
assessed toward the constraints taken into account and based on
the different variables being modeled. Taking the analysis to such
depth might even require restricting the sample further. This leads
over to directions for future research.
4.3. Research directions
Further conclusions are drawn regarding the modeling ap-
proaches taken as well as the so far weak link to empirical data:
• A critical link is the one to empirical research. While there is plen-
ty of empirical research on sustainable supply chain management
(see [42,69]), such data is not linked to the formal assessments of-
fered by quantitative models. While this might be challenging,
building on empirical data for the model development should pro-
vide a sound link into other streams of research within the wider
eld.
• There is also the open question about the popularity of models for
closed-loop supply chain management and reverse logistics and
not for the forward supply chain in research. The reasons can only
be speculated on. This cannot be concluded from the current body
of literature, but might be an issue for further analysis.• One further direction might be the link to supply chain contracts.
While a review of this topic has already been provided by Tsay etal. [74], this has not been connected to environmental and sustain-
ability issues. The single link to this topic is the analysis of shared
savings contracts ([7], as a further paper see [43]).
• Finally, the link into the supply chain management literature should
be strengthened. There is rarely a link into the literature on strate-
gic supply chain design (e.g. [68]), supply chain performance and
collaboration literature, which sees a number of interesting devel-
opments (see e.g. [72,37]). One such attempt has been made in a re-
cent paper by Wang et al. [75], who analyze supply chain network
design against environmental criteria. A further example links
green supply chain management to stock market performance [40].
The analysis needs further expansion. Future research can take up
some of the challenges to ll gaps in the still emerging intersection of
sustainability and supply chain management.
4.4. Future research questions
As a consequence of the previous analysis and research directions,
a number of broader research questions can be raised. Two broad
groups of research questions are proposed. The rst one relates to as-
pects of sustainability, while the second group integrates with supply
chain management thought.
Regarding questions on sustainability, it is obvious that the envi-
ronmental side has been addressed more often so far. This also
holds for the many contributions already looking at carbon based
emissions. Therefore, the link into the social dimension of sustainabil-
ity is emphasized here.
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• How can the social dimension be integrated into respective models?
Such approaches might have to build on the assessment of particular
social impacts, thereby reducing the overall complexity.• What is the interrelation among the social and the environmental
dimensions? This might be an issue where multi-objective optimi-
zation or the AHP allows reaching further conclusions.• Can the interrelation among all three dimensions of sustainability
be modeled? What are suitable approaches for doing so? Address-
ing this question, it would be worthwhile taking a look at functionsother than logistics, operations and supply chain management. This
should allow shedding light on the challenges but also respective
opportunities in research on sustainable supply chain management.
Questions on supply chain management:
• How does environmental and social performance impact supply
chain performance? While there are a number of contributions al-
ready on this question, a wider or more detailed analysis would
still be benecial.• How can contracts and supply chain cooperations be understood
further, so that sustainability issues are not just seen as trade-offs.
As the analysis in Table 3 is revealed, the assumption of trade-offs
dominates this stream of research. It might be interesting to see al-
ternative approaches and identify win–win solutions without beingoverly simplistic.
These research directions and questions would help developing
the eld further while only a selected set of them can be discussed
here.
5. Conclusion
The paper provides a review of the status of research on sustain-
able supply chain management applying (mathematical) modeling
techniques. The sustainability dimensions, the particular modeling
approaches taken as well as the empirical content as presented in
the papers have been assessed. It is evident that the environmental
dimension clearly dominates and social aspects are widely ignoredor interpreted in an unusual manner. Life-cycle assessment type stud-
ies and respective data form the backbone of the environmental de-
bate in the papers, while cost minimization still seems to dominate
the economic dimension. The different modeling approaches (equi-
librium models, multi-objective optimization and analytical hierarchy
process) form only a subset of the wider range of methods available.
The ndings of the paper summarize the status of research on apply-
ing modeling techniques in sustainable supply chain management
and offer insights into directions for future research.
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Stefan Seuring is a full professor of supply chain management at the University of Kassel, Germany. Previously, he worked at the Waikato Management School, Hamilton,New Zealand and was a visiting professor at the Copenhagen Business School. He holda PhD and habilitation from the Carl von Ossietzky-University of Oldenburg, Germany.He has published widely on sustainability and supply chain management.
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