One experiment examined the relationship between smoked marijuana and anxiety generated by the anticipation of a stressor paired with a salient, benign distractor. It was hypothesized that smoking one marijuana cigarette with an estimated &delta9-THC content of 26.25 mg, relative to placebo, would reduce anxiety generated by an anticipatory stressor paired with a benign distractor. In the experiment 14 marijuana users with a mean frequency of marijuana use per week of 2.07 (Range = 1-3) were administered one marijuana cigarette (active vs. placebo) per experimental session. A significant Drug × Session interaction was observed such that during the first experimental session, participants administered active marijuana reported non-significant decreases in negative affect, relative to placebo, while those administered active marijuana during the second experimental session reported significant increases in negative affect. This finding indicates that large individual differences in response to drug type (active vs. placebo) occurred within the participant sample. The results are discussed in terms of the influence of individual differences and contextual factors on the observed differential affective responses to &delta9-THC in order to identify which participants experienced the greatest benefit in negative affect reduction from &delta9-THC.