By reviewing causes of death among cohorts of various major disease entities or conditions, one may infer that a large majority of suicides are associated with a relatively small number of conditions. From the available follow-up studies, we might estimate that the following percentage of affected individuals will die by suicide: primary (endogenous) depression, 15 per cent; reactive (neurotic) depression, 15 per cent; alcoholism, 15 per cent; schizophrenia, 10 per cent; psychopathic personality, 5 per cent; opiate addiction, 10 per cent or more. Rough estimates of the number of suicides per year in the United States attributable to each condition might be as follows (using low incidence figures): depression, 12,900; alcoholism, 6,900; schizophrenia, 3,800; psychopathy, 2,000 (?); drug addiction, 900.