We followed 93 subjects from the San Francisco General Hospital Cohort for one year after notifying them of their HIV-1 antibody test results in order to examine self-disclosure, reactions, and concerns regarding disclosure. By one year post-notification, 92% of gay friends, 82% of primary sexual partners, 56% of new sexual partners, 46% of co-workers, 71% of physicians, 37% of dentists, 57% of psychotherapists, and 37% of family members had been told. Subjects were twice as likely to tell primary sexual partners, and more likely to self-disclose to all categories of persons (except physicians and dentists) than anticipated prior to notification. Least favorable reactions to seropositivity were from male family members and primary sexual partners, while seronegative subjects experienced unfavorable reactions only from some family members. Subjects were most concerned about health insurance (71%) and stigmatization (61%), but the latter declined (to 36%) at 12 months. Although encouraging, these findings suggest that self-disclosure should be discussed in both pre- and post-test counseling sessions.