This document discusses how networks, such as social networks and communities of practice, can be leveraged to support humanitarian aid efforts. It defines social networks as structures of interconnected individuals or groups, and communities of practice as networks that focus on sharing knowledge about a particular practice. Successful networks are reflexive and generative, focusing on learning and knowledge exchange. There are new online tools that allow for networking, which can change the dynamics of how networks operate. Cultivating effective communities of practice involves building on existing networks, focusing on an important domain, and developing both public and private sharing spaces.