It was hypothesized that individual differences in the adaptive value of narcotics would be paralleled by specific differences in ego functioning. Areas of ego functioning selected as particularly relevant to narcotic use were anxiety management and cognitive control. Sixty female residents of a State correctional institution constituted the study sample. Anxiety management characteristics were measured by using two self-report questionnaires (Anxiety Discharge Scale, including a total and six sub-scale scores, and Self-Perception of Impulsivity Scale). Cognitive Control characteristics were measured using six scores from four tests of cognitive function. The sample was divided into groups according to the degree and pattern of narcotic use. The prediction of group differences in anxiety management was strongly supported by the data analysis, while the prediction regarding cognitive control was not supported. Liking and using narcotics, regardless of the addiction dimension, was associated with a high level of anxiety discharge, especially characterized by a high degree of experienced anxiety. In addition, addiction involved a high impulsivity level. The two user groups were distinguished by a negative correlation between the more structurally mature discharge mechanisms and impulsive discharge, and were distinguished from each other by the relative prominence of one or the other type of discharge. Controlled users were characterized by stable high level discharge structures which permitted tolerance of a moderately high level of anxiety. The study instruments and statistical analysis methods are appended, and tabular data and references are provided. (Author abstract modified)