The current study examined the role of neighborhood disadvantage, perceived caregiver disapproval, and perceived peer disapproval in early initiation of substance use in a sample of 126 aggressive 9th graders (66% male; 79% African American). Findings suggested that perceived caregiver and peer disapproval as well as neighborhood disadvantage were associated with early substance use initiation. However, when associations were simultaneously examined, neighborhood disadvantage was the only factor related to early substance use initiation. Implications for findings are discussed.