We examine factors behind firms’ decisions to contribute to open standard setting. Our study highlights a novel explanation: firms seek to improve their positions in an interfirm cooperation network. In the wireless telecommunications standard-setting organization we study, firms develop new technical specifications in small committees. Our panel data analyses demonstrate that interorganizational network connections influence firms’ decisions to support committees. Additionally, firms are more likely to support committees when they are technologically distant from the firm that initiated the committee. We argue that standard setting presents opportunities for information exchange and for accessing complementary R&D assets through the cooperation network.