The Drug Abuse Screening Test (DAST) was designed to provide a brief instrument for clinical screening and treatment evaluation research. The 28 self-report items tap various consequences that are combined in a total DAST score to yield a quantitative index of problems related to drug misuse. Measurement properties of the DAST were evaluated using a clinical sample of 256 drug/alcohol abuse clients. The internal consistency reliability estimate was substantial at .92, and a factor analysis of item intercorrelations suggested an unidimensional scale. With respect to response style biases, the DAST was only moderately correlated with social desirability and denial. Concurrent validity was examined by correlating the DAST with background variables, frequency of drug use during the past 12 months, and indices of psychopathology. Although these findings support the usefulness of the DAST for quantifying the extent of drug involvement within a help-seeking population, further validation work is needed in other populations and settings.