Objective: To examine relations between neighborhood characteristics and psychological health, specifically whether neighborhood trust and cooperation buffers the effects of neighborhood disorder on depression and aggressive behavior. Methods: The sample was composed of 127 urban, African American young adults from Trenton, NJ. Results: The protective function of neighborhood social interactions depended on the outcome, such that trust and cooperation among neighbors moderated the effect of neighborhood disorder on aggression but not depression. Conclusions: Results confirm the importance of taking an ecological approach to study and promote the emotional and behavioral health of young adults living in urban communities.