Objective: To investigate links between girls' violent behavior, pubertal timing, and neighborhood characteristics. Method: A total of 501 Hispanic, black, and white adolescent girls and their parents were interviewed twice over a 3-year period (1995-1998). Violent behavior was assessed using the Self-Report of Offending Scale and pubertal timing was measured via menarche. This probability sample was drawn from Chicago. To characterize neighborhoods, neighborhood clusters were created. U.S. Census data were mapped onto each neighborhood cluster to represent levels of concentrated disadvantage, immigrant concentration, and residential mobility. The response rate was approximately 70%. Results: More than 25% of girls engaged in violent behavior at the second interview. Controlling for demographic indicators, previous violence, and other psychological factors, no differences were found in violent behavior as a function of menarcheal timing or neighborhood characteristics. Instead, results revealed that early maturers engaged in violent behavior only if they lived in neighborhoods characterized by high concentrated disadvantage. Early maturers in neighborhoods characterized by high concentrated disadvantaged engaged in three times the number of violent acts as early maturers in less disadvantaged neighborhoods. Depressive symptoms and previous violent behavior were also associated with girls' subsequent violent behavior. Conclusions: Results indicated that girls who experience a double vulnerability--early maturation and neighborhoods of disadvantage--are susceptible to engaging in violent behavior. This suggests the need for clinical evaluation to examine the implications of pubertal timing and the context of girls' behavior. J. Am. Acad. Child Adolesc. Psychiatry, 2004;43(12): 1460-1468. Key Words: puberty, neighborhood, violence, girls.