Drawing from theory and research on self-esteem as an important coping resource, we hypothesized that higher self-esteem would protect volunteers from the pernicious effects of stigma-by-association. In a longitudinal study of AIDS volunteers, higher anticipated stigma-by-association deterred the initiation of volunteerism for people with lower self-esteem. Three months later, greater stigma-by-association was related to less contact with an HIV+client in public (relative to private) settings, but only among volunteers lower in self-esteem. Moreover, greater relative public client contact predicted less overall satisfaction, but only for volunteers with relatively lower self-esteem. Implications for coping, stigma, and volunteer organizations are discussed.