The present study examined sense of identity (assessed using the Identity subscale of the Psychosocial Maturity Inventory) as a moderator of associations between stressful life events, behavioral/emotional problems, and substance abuse in a sample of 187 college undergraduates (67% female). Correlations showed evidence for positive associations between life stress and behavioral and emotional problems, negative associations between identity and life stress/behavioral and emotional problems, and a positive association between identity and GPA. For three outcomes--anxious/depressed problems, thought problems, and aggressive behavior--identity moderated the association, such that individuals with a stronger sense of identity reported fewer problems even when experiencing high levels of life stress. Primary results remained significant when controlling for age, global self-worth, and broad personality variables, and did not differ by gender.