Reports of the prevalence of depression among alcoholics vary from 3% to 98%; the authors attribute this variation to the use of different diagnostic criteria. They used clinical diagnosis, the Hamilton Depression Rating Scale, the Zung Self-Rating Depression Scale, and the MMPI to diagnose 35 men recently withdrawn from alcohol. The percentages of depression diagnosed were 8.6%, 28%, 66%, and 43%, respectively. The authors point out that the Hamilton, Zung, and MMPI scales are not diagnostic of depression in themselves and that accurate diagnosis of depression in alcoholics will reduce inappropriate treatment of nondepressed alcoholics and ensure careful treatment of the truly depressed.