To assess event-level associations between energy drink consumption, alcohol intoxication, and intention to drive a motor vehicle in patrons exiting bars at night.Alcohol field study. Data collected in a U.S. college bar district from 802 randomly selected and self-selected patrons. Anonymous interview and survey data were obtained as well as breath alcohol concentration (BrAC) readings.Results from logistic regression models revealed that patrons who had consumed alcohol mixed with energy drinks were at a 3-fold increased risk of leaving a bar highly intoxicated (BrAC≥0.08g/210L), as well as a 4-fold increased risk of intending to drive upon leaving the bar district, compared to other drinking patrons who did not consume alcoholic beverages mixed with energy drinks.These event-level associations provide additional evidence that energy drink consumption by young adults at bars is a marker for elevated involvement in nighttime risk-taking behavior. Further field research is needed to develop sound regulatory policy on alcohol/energy drink sales practices of on-premise establishments.