Using a mixed quantitative-qualitative research methodology the study investigated the relationships among early language and communication experience, maternal responsiveness and mental health outcomes in adolescence. Using a large existing, 15-year longitudinal database on children and adolescents with severe-to-profound deafness, 52 adolescents of hearing parents were identified for whom data on language experience, language skill, adolescent mental health functioning (culturally and linguistically adapted form of the Achenbach Youth Self Report and the Achenbach Child Behavior Checklist), interview protocols and videotapes was available. Three groups were identified: Auditory/Oral (AO) - youth who used spoken language, as did their mothers, in early childhood and adolescence; Sign Match (SM) - youth who signed in childhood and adolescence, as did their mothers; and Sign Mismatch (SMM) - youth who signed in adolescence but not in childhood, some of whose mothers signed in adolescence while others did not. It was hypothesized that better language scores in childhood and adolescence would be significantly associated with more favorable mental health outcomes; that AO and SM children would have more favorable mental health outcomes as compared to SMM children; and that AO and SM children would have better language scores in childhood and adolescence as compared to SMM children. The statistical analyses found partial support for each of the hypotheses.Six in-depth case studies were conducted to investigate the relationship between maternal responsiveness and mental health functioning. One typical case above the clinical cutoff, as defined by mental health outcomes, and one typical case below the cutoff, were selected from each communication group. Extensive interviews with mothers were conducted and documented at three times during the childhood phase of the study and were carefully reviewed to investigate a broad range of child and family characteristics, schooling, available resources and communication. Videotapes of mother-child and mother-adolescent interactions were also reviewed and mothers' responses and behaviors were examined for characteristics of maternal warmth and responsiveness. Together, the quantitative and qualitative results underscore the importance of an early and consistent mode match between deaf children and hearing mothers, as well as the importance of language and communication skills and warm maternal responsiveness.