The 1981 East Baltimore Mental Health Survey, part of the Epidemiological Catchment Area (ECA) program, provided data for the examination of the prevalence of delirium in the general adult population. From an original 3,841 households surveyed, 810 individuals were selected for psychiatric evaluation and, of these, 6 individuals were diagnosed as suffering from delirium. The estimated prevalence of delirium in the population was .4% and 1.1% among those 55 years of age and over. A comparison of these cases with cases of diagnosed dementia and individuals of the same age range who did not receive a psychiatric diagnosis found that those with a diagnosis of delirium suffer from a greater number of medical conditions, take more prescribed medications, and have a higher level of physical disability.