Psychotherapists of different theoretical persuasions use systematically different profiles of verbal response modes. However, clients tend to use very similar profiles, regardless of what their therapist does. Disclosure comprises the largest part of this common client profile, and it distinguishes the client role from other roles. Higher levels of client disclosure are associated with external observers' ratings of good psychotherapeutic process, though not necessarily with participants' ratings of session depth and value. Relatively high levels of client disclosures are associated with participants' judgments that a session was relatively rough, difficult, and dangerous. And clients who are more depressed, anxious, or generally psychologically distressed have higher levels of disclosures in psychotherapy. A helpful analogy suggests that client disclosure may be related to psychological disturbance as body temperature and white blood cell count are to physical infection. In the case of physical infection, a fever and an elevated leukocyte level are parts of the body's immunological response--mobilizing to fight the infection. Disclosure may be, analogously, part of a natural corrective or protective reaction to psychological disturbance. Primarily, it helps regain psychological homeostasis, and secondarily, it serves as a symptom of distress. This analogy makes sense of the distinctively high level of disclosures in therapy and of the theoretical and empirical association of disclosures with "good process". It is also consistent with the correlation of disclosures with psychological distress and discomfort. (Author/JAC)