More prevention effort is required as the HIV epidemic increases among gay and transgender African American youth. Using ecological systems theory and an integrative model of behaviour change, this study examines the sexual behaviour of gay and transgender African American young people as embedded within the unique social and structural environments affecting this population. Also examined is the important role played by mobile technology in the social and sexual lives of individuals. Seven focus groups were conducted with 54 African American young adults in a northeastern U.S. city. The findings provide a rich examination of the social and sexual lives of gay and transgender African American youth, focusing on the social environment and the impact of the environment on sexual risk behaviour.