Men who have sex with men (MSM) is an inclusive term used to refer to phenotypic males who have insertive or receptive sex (penile-anal or penile-oral) with other phenotypic males, including people who are transgender or have other gender identities. MSM may report their sexual orientation as homosexual, bisexual, heterosexual, or something else, but this stated sexual orientation may not align with their sexual attraction or behaviors. Several health conditions disproportionately affect MSM compared with age-matched heterosexual men, including HIV infection, anal cancer, syphilis, and depression. Clinicians should use culturally sensitive questions to obtain a comprehensive sexual history and assess sexual risk. MSM should receive regular screening for HIV, hepatitis B and C, gonorrhea, chlamydia, and syphilis. Vaccinations for hepatitis A and B and human papillomavirus should be offered. MSM may benefit from preexposure prophylaxis to prevent HIV infection, postexposure prophylaxis to reduce the risk of HIV transmission, and counseling on safer sexual practices. Screening for anal cancer associated with human papillomavirus may be performed by digital anal rectal examination, although the optimal screening strategy has yet to be determined. Clinicians should also consider more frequent screenings for mental health issues in the MSM population because the rates of depression, suicide, substance use, and other psychosocial issues are higher than those of the general population.