Recent research suggests that gay, lesbian, bisexual, and transgender (GLBT) persons are at greater risk for mental health problems, including suicidal and nonsuicidal self-injury, than heterosexuals. However, few studies have investigated factors that may be linked to this increased risk. This study investigated interpersonal violence, victimization, and discriminatory events as possible predictors of suicidal and nonsuicidal self-injury in a sample of sexual minorities (i.e., a GLBT sample). Participants were 1,126 self-identified gay, lesbian, bisexual, and/or transgender (GLBT) individuals who responded to an Internet-based survey. Results indicated that both experiences of interpersonal trauma and sexual discrimination were associated with increased likelihoods of engaging in suicidal and nonsuicidal self-injury. In addition, participants at the greatest risk were those experiencing high levels of both interpersonal trauma and sexual discrimination. Clinical implications of these results are discussed.