The prevalence of relapse to alcohol or other drug use and prevalence and severity of depressive symptoms were measured cross-sectionally in different age groups of alcohol and drug abusers at one, six, and twelve months post-discharge. Relapse rates increased over time since discharge for all age groups (17-29, 30-39, 40-49, and 50+ years). However, no differential effect of age was found on relapse rates at each of the three post-discharge intervals. Rates of depressive symptoms increased over time since discharge only for the youngest age group. Mean depressive symptom scores increased over time since discharge only for the 17-29 and 50+ age groups. There were significant differences between age groups in rates of depressive symptoms at six and twelve months post-discharge and on mean depressive symptom scores at one, six and twelve months post-discharge. In addition, for abstinent and for relapsed subjects, there were significant differences between age groups in rates of depressive symptoms and mean depressive symptom scores. Higher rates of depressive symptoms were found in relapsed than abstinent subjects at the younger ages (17-29 and 30-39 years), with mean depressive symptom scores being higher for relapsed than abstinent subjects in all age groups.