This IDC Insight discusses how enterprise social networks (ESNs) will support collaboration inside and outside an organization. ESNs will come to encompass all social solutions and networks that are active in an organization, including independent social networks that may exist for ad hoc collaboration and business applications with embedded social capabilities, as well as capture the broader influence of networks active inside and outside the firewall. Forming the core of the enterprise social backbone, the ESN becomes the new age replacement for a static intranet as companies move from the one-directional style of communication to a more collaborative and informal means of communication.