The tragic incidence of substance abuse has recently reached epidemic proportions and is being dramatically felt throughout the United States. Despite heroic efforts at both prevention and intervention, virtually no segment of our society has been exempted from its dire consequences. The purpose of this study is to investigate the prevalence, distribution and impact of substance abuse as related to selected variables. The study involves the identification of demographic correlates and other characteristics of the substance abuse population, as well as an exploratory examination of the way these persons are situated and embroidered into the larger social demographic fabric. The primary data source was the National Health Interview Survey (NHIS) used to generate information for the National Center for Health Statistics. The sample for this study was comprised of 62,052 persons who had been interviewed from 23,838 households in 1986. The estimates calculated for this report, however, were based on a projected population of 171,800,848 persons of which 113,818 were identified as being substance abusers. The findings in this study suggest that substance abuse must be understood in terms of its relationship to age, formal education, and marital status. These variables along with income, appear to be the strongest correlates of substance abuse.