This study evaluated behavioral and self-report indices of impulsiveness in pathological gambling substance abusers (n=27), non-pathological gambling substance abusers (n=63), and non-pathological gambling/non-substance abusing controls (n=21). The Bechara card task measured preferences for decks of cards that ranged in magnitude and probability of delayed and immediate rewards and punishers. The Stanford Time Perception Inventory (STPI) assessed orientation to the future, the Zuckerman Sensation Seeking Scale evaluated sensation seeking, and the Eysenck and Barratt scales measured impulsivity. A Principal Components analysis revealed that these personality measures comprised three distinct measures of impulsivity: impulse control, novelty seeking and time orientation. Linear contrast analyses revealed that substance abuse and pathological gambling resulted in additive effects on the impulse control and time orientation factors, but not on the novelty-seeking scale. Performance on the card task did not correlate with any of the three factors derived from the personality scale scores, but the presence of both substance abuse and pathological gambling had an additive effect on preferences for decks containing greater immediate gains but resulting in large punishers and overall net losses. These results provide further evidence of an association among substance abuse, pathological gambling, and impulsivity.