Clinical research on sexual behavior has increased dramatically in the last decade. Connected with these efforts has been the need to understand more about sexuality in order to help reduce the spread of human immunodeficiency virus. This report details the results of a study of men (N=536) aged 18 to 30 years, who reported having had sex with a man and with a woman in the past 3 years. Approximately 50 percent of the respondents were white and 50 percent were African American. Follow-up interviews with nearly 220 men were conducted one year later. Discussed are issues of sexual orientation, diversity among bisexual men, society's valuation of bisexuality, identity confusion, relationships issues, bisexuality and HIV/AIDS, and implications for clinical practice. Many of the problems experienced by non-heterosexual persons are rooted in the lack of societal tolerance for uncommon sexuality. Bisexual clients may feel extreme alienation as they confront pervasive unacceptance in both the heterosexual and the homosexual communities. Bisexual clients' marginalization is compounded by the lack of bisexual communities and the subsequently fewer options for external support. Clinicians can help bisexual clients' confusion by framing it as a normal, adaptive response to society's dichotomous view of sexuality. Contains 30 references. (RJM)