Sexual transmission of human papillomavirus between women has been postulated on the basis of reports of abnormal Papanicolaou smears in women who reported no prior sex with men and by studies using amplified deoxyribonucleic acid technology for human papillomavirus detection. To review the current knowledge of the epidemiology of human papillomavirus and the Papanicolaou smear screening practices among women who have sex with women, studies were identified from a search of the MEDLINE database from January 1980-June 1999. Several factors, including prior or concurrent sex with men and sexual behaviors between women, validate the possibility of human papillomavirus infection among women who have sex with women, and data support that human papillomavirus transmission also occurs. Limited data indicate that the frequency of routine Papanicolaou smear screening among women who have sex with women may be suboptimal relative to heterosexual women. Education of women who have sex with women and the providers of their health care should counter any assumptions that sex between women confers no risk of human papillomavirus transmission. Women who have sex with women should receive Papanicolaou smear screening in accord with current guidelines.