Alliances are often formed as a response to challenges from both market and social forces. Although the resource dependence logic posits that firms enter into alliances to stabilize resource flows between different markets and also to increase market power in their primary industry, it remains unclear whether the social power of firms, generated from alliance networks, may motivate firms to respond differently to the dependence logic of alliance formation. By incorporating social network theory, we argue that a firm’s social network advantages in the primary industry may serve as critical contingency conditions of the dependence logic. Analyses of firms in the U.S. computer industry from 1994 to 2007 suggest that a firm’s centrality advantage marginally reduces the positive effects of market dependencies on alliance formation, whereas a firm’s brokerage advantage enhances the market dependence effect.