Interorganizational relationships enabled by information systems (IS) are formed under various contingencies. Past research in interorganizational collaborations has benefitted from employing rational choice and institutional theory separately but as organizations face dual pressures to improve performance and gain legitimacy in their social environments a fuller explanation must encompass both perspectives. This study examines the question of why ICT-enabled collaborations form in the public safety domain by employing rational choice and institutional theory perspectives as complementary. This study specifically examines the possibility of a neighbor effect in stimulating the establishment of interagency policing collaborations, while also attending to economic, geographic, and demographic factors influencing this decision to join-up. When completed, this study will contribute to IS knowledge by extending homophily research into the domain of public safety IS, and by incorporating institutional and rational perspectives as an analytical platform from which to apply findings from the public to the private sector.