Women who have sex with women (WSW) comprise a diverse group of people who evidence a spectrum of sexual identity, sexual behaviors, sexual practices, and risk behaviors. WSW are at risk of acquiring a diversity of sexually transmitted infections (STIs) from current and prior partners, both male and female. Notably, human papillomavirus (HPV) is sexually transmitted between female partners, and Pap smear guidelines should be followed in this group. Bacterial vaginosis is common among WSW. WSW should not be presumed to be at low or no risk for STIs based on sexual orientation, and reporting of same sex behavior by women should not deter providers from considering and performing screening for STIs, including Chlamydia trachomatis, according to current guidelines. Effective delivery of sexual health services to WSW requires a comprehensive and open discussion of sexual and behavioral risks, beyond sexual identity, between care providers and their female clients. © 2012 Springer Science+Business Media, LLC.