While previous research has found project buying to be distinct from other buying situations, in that it typically involves a multi-organizational network, to date there has been very little empirical research on this phenomenon. Our aim in this paper is therefore to investigate the structure and decision-making processes of the project buying network during the project cycle and its interactions with project sellers. We first develop a preliminary conceptual framework for analyzing the project buying network, which is then applied to a comparative case study of three development projects. The findings from the case study allow us to propose a revised conceptual framework for analyzing the dynamics of the project buying network during the project cycle, as well as interaction with sellers. Our findings also contribute an understanding of development projects, in particular the role of financiers.