While top management support is critical to the success of information technologies (IT), little is known about how differences and similarities between the CEO and the CIO influence such support. Accordingly, this research examines the heterogeneity between CEO and CIO as antecedents of organizational support and its impact on competitive position in regards to IT in stable and unstable environmental context. A survey instrument was developed and distributed to matched CIO and CEOs. The findings indicate that the CEO/CIO heterogeneity in terms of experience positively impacts the organizational support for IT. Also heterogeneity of the functional background has a negative impact on the long term support for IT in stable environment. With regards to the final outcome, the organizational support for IT positively influence the competitive position of the firm in regards to IT usage. The results provide guidance to both CIO and CEO regarding the type of support needed in different organizational context.