Research has compared lesbian and heterosexual women across a variety of health outcomes and concluded that health disparities exist across many samples and methodologies. Lesbians are at increased risk for a variety of health problems compared with their heterosexual counterparts. Recent reports published by the Institute of Medicine and the U.S. Department of Health and Human Services have classified lesbians and other sexual and gender minorities as an at-risk and underserved population. This entry examines some of these health disparities as well as the reasons for them. In addition, the entry provides recommendations for culturally affirmative practices and future research.