This study examines a homeless social movement organization-Shelter Now-that is attempting to influence policy and empower homeless people in a small California city. Interviews with Shelter Now leaders, service providers, and city and county policymakers explore the role of Shelter Now in city politics. Specifically, I analyze Shelter Now's political organizing strategies and tactics, its relationships with elites, and the outcomes of its efforts to change local homeless policy. By considering Shelter Now's activities through the lens of social movement theory, I suggest that assessing the group's victories and its defeats serves to sharpen our sense of the limitations of homeless groups and to focus social movement theory more centrally on such limitations. Shelter Now faces significant obstacles in trying to organize homeless people politically; the homeless suffer police reprisals and loss of shelter and other services as a result of their activism. Service provider and police repression of Shelter Now reveals the extreme social and political marginalization experienced by groups like the homeless; such marginalization translates to a precarious and sometimes limited form of grassroots activism.