This article discusses how the extension of network governance influences the de facto independence of regulatory agencies. Assuming that agencies gain de facto independence vis-à-vis the government when they experience a substantive increase in their reputation, we argue that agency participation in international governance networks contributes to strengthen agency domestic positions due to organizational learning and the expansion of expert knowledge involved in such interactions. Based on a case study of the Spanish nuclear regulatory agency (Nuclear Safety Council [CSN]), the article highlights how its involvement in international governance networks promoted the agency’s de facto independence during the 2000s.