The diverse life experiences of contemporary lesbians are shaped by women's differing ties to two social worlds, the majority heterosexual society and the minority subculture of the lesbian or sexual-minority world. This article presents a detailed conceptual analysis of a dual-identity framework that emphasizes lesbians' simultaneous affiliations with both lesbian and mainstream/heterosexual communities. The usefulness of this approach is discussed, with emphasis on implications for understanding individual differences in exposure to gay-related stress and mental health. Results from a survey of 116 lesbians showed that scores on measures of Lesbian Identity and Mainstream Identity were not significantly correlated with each other. Both lesbian and mainstream identities were significantly related to lesbians' reported experiences of discrimination, feelings of internalized homophobia, and life satisfaction. Limitations of the dual-identity framework and suggestions for future research are considered.