In emergencies, information sharing among and between officials, volunteers, and citizens is essential for effective recovery and management. Recently, volunteers and others have been using community technology centers, community wireless networks, and end-user social technologies such as blogs and Wikis to prepare for emergencies and communicate and coordinate response when they happen. This paper argues that there is a need for a research agenda that combines our knowledge of community informatics with the principles of disaster management to understand how social networks form and mobilize in disasters and how information and communication technologies should be designed and deployed to engage, inform, and mobilize those volunteer and citizen networks.