In this paper we present a critical analysis of the concept of network governance and evaluate its use in implementing policies of sustainable development. In particular, we analyze the network approach proposed in the European Commission’s White Paper on governance and its role in environmental policy integration. Relying on research on the concept of selforganization in complex adaptive systems, we show the limits of a concept of network governance that is solely based on self-organization. On this basis, we argue to complete the current network approach to sustainable development with initiatives that foster social learning in the governance networks. As an example of such an initiative, we examine the case of the recent experiment of Sustainability Impact Assessments.