Of the 4,624 Lebanese citizens diagnosed as psychiatric February 15-August 15, 1964, 315 were drug addicts. Patterns of prevalence showed a rapid turnover and high recidivism among addicts who came to psychiatric attention. The distributions of these patients by age, sex, marital status, income, education, and religion, and by the subcategories of addiction, are presented. Referral and treatment processes are described. There was a striking concentration of addicts among males, in the lower income group, and among Moslems. (15 ref)