The relationship of drug use to the Adlerian concept of birth order was the focus of the present study. Generally, the objective was to determine whether there was a statistically significant overrepresentation of latter born children in a sample of drug addicts. The subjects were 95 male patients of the Mental Health Clinical Research Center of Fort Worth, Texas, who were randomly selected from the Center's total population of 273. All the subjects were classified as drug addicts by the Narcotic Addict Rehabilitation Act of 1966. Within the sample was a mixture of Anglo-Saxon, Negro, and Latin males of different ages, educational backgrounds, family incomes, and work experience. “Only children” were not used in this study because they constitute a distinct group and probably differ from first borns and latter borns in important ways. Birth order statistics from the sample were compared with national statistics on birth order which were derived from data given in Population Characteristics, Fertility of the Population, January 1969. A five-celled chi-square contingency test was used to evaluate the null hypothesis that there was no relationship between birth order and drug use in the sample under investigation. The results of the statistical analysis supported the null hypothesis; that is, there was no relationship between the Adlerian concept of birth order and drug use. In addition to the main hypothesis, racial background and family income were also considered as possible variables influencing the latter born child in the taking of drugs. Only individuals from Latin-American family backgrounds gave any suggestion of a relationship between drug use and birth order within a specific racial group. Family incomes did not appear to influence significantly an overrepresentation of latter born children in the taking of drugs. Although the present study did not support the main hypothesis, a relationship may exist; however, it was not found in this study.