Psychological characteristics of 384 adult males classified as Type A or Type B by the structured interview were examined. Subjects classified Type A differed significantly from subjects classified Type B on a number of psychological scales including measures of aggression, autonomy, extroversion, and impulsiveness but not on measures of psychological distress. The extent to which pencil and paper questionnaire assessments of Type A differ from structured interview ratings was also studied. Correlations between the various Type A questionnaire scales and the structured interview were found to be notably low. The use of Type A questionnaires and implications for Type A interventions are discussed.