Self-esteem, generally regarded as an important indicator of adolescents' mental health, was assessed by a self-report questionnaire in a school sample of 593 subjects who had been assessed at 3 time points over 7 years between 11 and 25 years of age within the Zurich Psychology and Psychopathology Study (ZAPPS). Cross-lagged panel analyses of the longitudinal data from ZAPPS indicated that self-esteem was predictive of internalizing problems and had an impact on internalizing symptoms when the analyses were adjusted for coping behavior, efficiency of social networks, and impact of stressful life events. Self-esteem was also stable (r = .37-.60) within the observed age range, after controlling for prior levels of the predicted variables. The findings support the impact of self-esteem on mental health and indicate the importance of addressing self-esteem in prevention and intervention programs.