Leaders in disaster response are finding it necessary to adapt to a new reality. Although community actions have always been the core of the recovery process, collective action from the grassroots has changed response operations in ways that few would have predicted. Using new tools that interconnect over expanding mobile networks, citizens can exchange information via maps and social media, then mobilize thousands of people to collect, analyze, and act on that information. Sometimes, community-sourced intelligence may be fresher and more accurate than the information given to the responders who provide aid. This report explores approaches to the questions that commonly emerge when building an interface between the grassroots and government agencies, with a particular focus on the accompanying legal, policy, and technology challenges.