The study of non-suicidal self-injury (NSSI) has focused largely on identifying diagnostic correlates and the functions of this behavior; however, little is known about the broader range of factors related to NSSI. We examined a wide array of factors hypothesized to correlate with non-suicidal self-injury (NSSI) and provided a qualitative analysis of adolescents' self-reported motivations for starting and stopping this behavior. Participants were 64 adolescents with a history of NSSI and 30 comparison adolescents without such a history matched on age, sex, and ethnicity recruited from the community and assessed during one laboratory visit. The presence of NSSI was associated with a family history of suicidal ideation, violence, and drug and alcohol abuse, but not with more general forms of psychopathology. NSSI also was associated with the presence of in utero complications, the occurrence of non-injurious repetitive behaviors during childhood, and endorsement of a homosexual or bisexual orientation. Self-injurers reported getting the idea to self-injure from peers (38%) more often than any other source, and most (78%) reported at least one reason for wanting to stop self-injury. Less than half were currently receiving treatment. This exploratory study provides new information about the correlates of NSSI that has implications for research and clinical work in this area.