This study proposed a model to examine the interorganizational relationship factors on the technology diffusion in supply chain networks whereby a firm's adoption decision is influenced by information from physical and social proximity with others as well as its own attributes. To test several hypotheses developed in this context, this paper analyzed the data set of US consumer packaged goods companies adopting an inventory tracking technology in a retail supply chain and found that a potential adopter's decision is largely influenced by the social proximity with prior adopters in a network over time, while a firm's likelihood of adoption at the initial period is mainly determined by its own attributes.