This paper reviews research conducted over the past 25 years on the therapist's use of self-disclosure and the therapeutic relationship. Various definitions of self-disclosure are reviewed, the content of therapist disclosures is considered, and the choice to disclose is examined. Methods of measuring self-disclosure are discussed and research on therapist self-disclosure is reviewed. Findings from actual and analogous therapy situations are discussed which demonstrate consistent positive client responses to therapist self-disclosure. In contrast, surveys of therapists are reviewed which show a large variance in therapists' positions on the topic of self-disclosure. These findings are discussed within the context of the therapeutic process. Three components of the therapeutic relationship are identified: the therapeutic alliance, the transference relationship, and the real relationship. It is suggested that the difference between clients' and therapists' opinions on the value and appropriateness of therapist self-disclosure can be explained partially in terms of the therapists' greater understanding of the transference phenomenon and their deeper recognition of the tension between the needs to be be both neutral and real with clients. It is concluded that the varying degrees of emphasis that therapists place on the transference relationship parallel the disagreements among therapists of differing orientations over their beliefs about the place of therapist self-disclosure in psychotherapy, such that the more the transference relationship is emphasized, the less self-disclosure is valued. (41 references) (NB)