Measures of aggressive behavior, antisocial personality, criminality, and impulsivity were obtained on a sample of 85 drug abusing volunteers for studies at the Addiction Research Center in Baltimore. Measures included the Buss-Durkee Hostility Inventory, Diagnostic Interview Schedule Antisocial Personality Disorder diagnosis, Elliott-Huizinga Lifetime Events Scale, Eysenck's Impulsiveness-Venturesomeness-Empathy scales, and a laboratory measure of aggression patterned after the Buss 'aggression machine'. All of the self-report measures of aggression and antisocial personality were moderately correlated with each other, but did not correlate with the laboratory aggression measure. This laboratory measure, nevertheless, made a significant contribution to the prediction of certain substance abuse diagnoses over and above the contributions of the other measures.