Post-mortem psychiatric diagnoses are compared in two cohorts of male suicides from St. Louis (1956-1957) (Robins, 1981) and San Diego (1981-1982) (Rich et al., 1986). Similar structured interviews and diagnostic criteria had been used in both assessments. Substance/alcohol abuse has remained the major diagnosis in suicides under age 60. Rates of depressive disorder alone have decreased overall, due mostly to decreased rates in the elderly. Thus, depression occurs more frequently in younger ages. Comorbid depression and substance/alcohol abuse has also increased in younger ages. Implications in terms of the so-called 'cohort effect' are discussed.