Convened by the AIDS Foundation of Chicago, the Canadian AIDS Society, the Community HIV/AIDS Mobilization Project and the Global Campaign for Microbicides in the spring of 2005, the International Rectal Microbicide Working Group (IRMWG) is currently a coalition numbering over 360 advocates, policymakers and leading scientists from 35 countries on 5 continents working to advance a robust rectal microbicide research and development agenda. The IRMWG hosts a moderated listserv and sponsors regular international conference calls featuring presentations on the latest in rectal microbicide research.