Aims: Mood and presumed sub-cortical and frontal lobe related traits were assessed in 100 in-patients undergoing treatment for substance use disorders and in a community control sample of 107 social drinkers. Methods: Participants completed self-report measures of mood, alexithymia, dispositional mindfulness, frontal systems functioning, impulsivity, sensitivity to rewards and punishments, alcohol use, illicit drug use and demographic characteristics. Results: Multivariate analysis of covariance (MANCOVA) controlling for age, education, previous serious head injury and gender revealed highly significant differences (p < .0001) between clinical and control groups on all dependent measures. The clinical group scored significantly higher on depression, anxiety, stress, alexithymia, frontal systems dysfunction, reward sensitivity, punishment sensitivity and impulsivity, and lower on dispositional mindfulness, than the control group. Time in treatment was significantly correlated only with levels of depression, anxiety and stress, supporting the relative stability of the trait measures. Conclusions: Results are consistent with the notion that substance use disorders are linked to frontal lobe dysfunction and associated traits, although the current findings cannot determine whether such characteristics predated or post-dated disordered substance use.