Several recent studies have taken an institutional approach to e-commerce or EDI diffusion and assimilation (Purvis et al. 2001, Chatterjee et al. 2002, Teo et al. 2003). It is well known that mimetic, coercive, and normative institutional pressures existing in an institutionalized environment may influence organizations’ predisposition toward an IT-based interorganizational system (Teo et al. 2003). Mimetic pressures are observed when firms adopt a practice or innovation imitating competitors (Soares-Aguiar and Palma-Dos-Reis 2008). Coercive pressures are a set of formal or informal forces exerted on organizations by other organizations upon which the former organizations depend (Dimaggio and Powell 1983). Normative pressures come from dyadic relationships where companies share some information, rules, and norms. Sharing these norms through relational channels amongst members of a network facilitates consensus, which, in turn, increases the strength of these norms and their potential influence on organizational behaviour (Powell and DiMaggio 1991).