Case study Towards a multi-dimensional approach to supply management: a comparative case study Carlos Brito and Catarina Roseira Faculty of Economics, University of Porto, Porto, Portugal Abstract Purpose – The article aims at contributing to a better understanding of the interdependence between supply management and the strategic position of the buying firm. Design/methodology/approach – The research follows a qualitative analysis of two cases: Adira, a family-owned manufacturer of machinery to cut steel, and Vulcano, a manufacturer of instantaneous house gas water-heaters and boilers. Findings – The article finds that supply management decisions depend not only on the network position of the buying firm, but also on the network vision of its managers. Research limitations/implications – The study is based on two contrasting cases. Further research should develop and test the findings by using other cases and methodological approaches more quantitative in nature. Practical implications – The article has three major practical implications: supply management should integrate three levels of decisions: dyadic, portfolio and network decisions; supply management does not depend solely on firms’ strategic positioning and strategies, but also on managers’ network theory about the role and capabilities of suppliers; and “no strategy” can also be a strategy. Originality/value – The study was conducted on the basis of a multi-dimensional model that integrates three levels of analysis: dyadic, portfolio and network. Keywords Supply chain management, Buyer-seller relationships, Networking Paper type Case study Introduction Supply management has received special attention over the past decade. Since the seminal work of Ha ˚kansson and Johanson (1993), a number of researchers have focused their efforts on the understanding of supply chain networks (see Ford and McDowell, 1999; Mo ¨ller and To ¨rro ¨ nen, 2000; Ho ¨lmen and Pederson, 2003). In general, these works focus on supply relationships in the context of the network in which firms are embedded. However, important issues regarding supply management and its effects on the performance and strategy of the buying firm seem not to have been fully investigated. The purpose of this article is to contribute to a better understanding of the interdependence between supply management and the network position of the buying firm. On the basis of the conceptual framework of the IMP group, the article embraces a model that is used to analyze supply networks in the context of two cases: Adira, a Portuguese family-owned manufacturer of machinery to cut steel; and Vulcano, a manufacturer of house gas water-heaters, that is fully owned by the international group Robert Bosch. The article is divided into five sections. The first section elaborates on the interaction and industrial network approach’s basic concepts and complements it with the work conducted by Brian Loasby on organizational capabilities. The following section presents a model of supply chain networks that results from a conceptual extension of the existing literature and how it can be furthered in order to explore some relevant issues that still remain relatively obscure. The next section three briefly addresses the research methodology that underlies the case analysis, which is presented in the penultimatesection. The last section includes a number of recommendations for managers. Capabilities: the missing link between functions and relationships Several authors (see Ha ˚kansson and Johanson, 1993; Anderson et al., 1994; Ha ˚kansson and Snehota, 1995; Ford and McDowell, 1999; Mo ¨ller and To ¨rro ¨nen, 2000; Ho ¨ lmen and Pederson, 2003) have studied relationships’ functions in industrial networks. In general, they have concluded that such functions have both direct and indirect effects. The first concerns effects within the dyadic relationship itself, independent of other parties’ links to the partners involved. Cost reduction, quality, volume and safeguard functions are examples of direct functions. On the other hand, relationship The current issue and full text archive of this journal is available at www.emeraldinsight.com/0885-8624.htm Journal of Business & Industrial Marketing 22/1 (2007) 72–79 q Emerald Group Publishing Limited [ISSN 0885-8624] [DOI 10.1108/08858620710722842] 72