This study examined the relationship between environmental characteristics and heavy episodic drinking by examining college students' last drinking events. For this study, 409 undergraduate students attending a large public university were randomly selected. Students were asked to report on their last drinking event within the 30-day period prior to being surveyed. There were 274 drinking events analyzed. Bivariate analyses and multiple logistic regression analysis were used to identify contextual factors predictive of heavy episodic drinking in specific drinking events. Drinking with friends, drinking beer and hard liquor, and having many people intoxicated at an event were predictive of heavy episodic drinking events. Dating events were protective of heavy episodic drinking. Implications for future research and prevention are discussed.