Major Issues Views regarding intentional self-disclosure are closely linked to theoretical orientation; some believe it is beneficial and others suggest that it is potentially harmful. Specific forms of therapist self-disclosure exist, and it has been suggested that self-disclosure of sexuality can be therapeutically beneficial when both therapist and client identify as gay. Methods A literature review was conducted focussing on the role of models, assertion and evidence within the area of therapist self-disclosure. A qualitative research study was also conducted with five clinical psychologists. Semistructured interviews were used to explore participant's views and experiences of disclosing their sexuality to gay male clients. Data was analysed using interpretative phenomenological analysis (IPA). Findings The research and theoretical evidence in the literature review suggested that intentional therapist self-disclosure can be helpful, unhelpful or both. Limitations of the reviewed research evidence were noted, and it appears that use and non-use of self-disclosure is based primarily on theoretical constructs and personal perspectives. These issues are discussed in relation to clinical practice. The results from the research study suggest that gay clinical psychologists felt that direct disclosure of their sexuality could have beneficial and potentially negative effects on psychotherapeutic work with gay clients. The analysis revealed six superordinate themes: being gay in a straight world; disclosure and the therapeutic agenda; the contexts of disclosure; other ways of knowing; disclosure of sexuality: a big deal; and the invisible curriculum. These findings are discussed in relation to previous research, implications for practice and training. Conclusion The findings of the literature review and research study indicate that therapist self-disclosure is a complex area, and may be beneficial or unhelpful within therapy. Future empirical research on therapist self-disclosure is necessary, however the current work provides some evidence in relation to the disclosure of sexuality to clients.