Though evidence suggests that bisexuals may outnumber homosexuals and that bisexuality is increasing, there is a paucity of research on this group. Further, because researchers have included large numbers of bisexuals as ôhomosexualsö in their studies of homosexuality, we cannot even be sure of what we know about homosexuals. The author examines a Varity of issue: sex differences, life-styles, discrimination, and changes in sexual orientation over the life span, etc. Four beliefs about bisexuals are presented and examined: Bisexuality as: (1) real and natural, (2) transitory (the bisexual will return to his or her original orientation), (3) transitional (the bisexual will become exclusive at the orientation opposite to his or her original orientation), and (4) homosexual denial.