This document provides an executive summary of guidelines for preventing and treating HIV and other sexually transmitted infections among men who have sex with men and transgender people. It notes that these populations face disproportionately high rates of HIV and STIs. It recommends evidence-based interventions for health systems and programs to address this issue, including increasing access to HIV testing, prevention of sexual transmission, behavioral interventions, substance use treatment, HIV care and treatment, and prevention and care of other STIs. The guidelines are intended to help national HIV programs, organizations, and health workers improve their response to the epidemic in these populations.