Chapter 2 Organizing for Collaborative Procurement: An Initial Conceptual Framework Elmer Bakker, Helen Walker and Christine Harland INTRODUCTION Forming collaborative procurement arrangements is suggested to be an increasing trend in purchasing and supply (Carter et al., 2000; Nollet & Beaulieu, 2003; Walker et al., 2003). There is increasing international interest in collaborative procurement arrangements in the public sector in countries such as Canada, Finland, Germany, the Netherlands, the UK, and the U.S. (Aylesworth, 2003; Essig, 2000; Kamann, van der Vaart & de Vries, 2004; Kivisto et al., 2003; Nollet & Beaulieu, 2003; Schotanus & Telgen, 2005). Recent examples in the UK are found in the National Health System (NHS), the police, the Highways Agency and local government, varying from exchanging information and experiences, buying together through an electronic marketplace, using lead-buying arrangements, or through installing a separate buying organization. This increased attention in the UK public sector has been triggered by a central government efficiency review (Gershon, 2004). Although some preconditions for effective collaboration can be found in the literature (Aylesworth, 2003; Rozemeijer, 2000), an overall model that shows which form is suitable in which situation is not in evidence. The aim of this chapter is to develop an initial conceptual framework that can assist in determining when particular forms of collaborative procurement are (ideally) appropriate. BACKGROUND Collaborative procurement in this chapter is seen as horizontal cooperation between organizations, the bringing together (or pooling) of the purchasing functions of two or more organisations (Essig, 2000).