The 1980s witnessed the development of community-based AIDS service organizations across North America. This article looks at how these community groups can become increasingly formalized and professionalized over time. The article is based on an in-depth examination of one AIDS organization in Ontario, Canada. Interviews were conducted with staff members, volunteers, and board members of the organization, as well as with knowledgeable individuals in the surrounding community. The article identifies ways in which the organization has changed over time, and highlights some of the forces which propel these changes. The article concludes with a discussion of the political implications of the increased formalization of community AIDS groups.