This study adds to existing knowledge about information technology diffusion within organizations by examining the effects of social embeddedness on behavior of individual diffusers. Building on a social capital perspective of relationships, the authors theorize that individuals make intentional decisions to promote or suppress an innovation contingent on the nature of their relationship(s) with the potential adopters. Hypotheses regarding the likelihood of diffusion of an IT innovation through friendship, advice and multiplex friend and advisor relationships at early versus later stages in the diffusion process were tested using social network and panel survey data in two organizations. Results support predictions that individual diffusion behavior is contingent on the relation type and the progress of the innovation in the organization.