Objectives: To assess electronic nicotine delivery system (ENDS) use and vaping behaviors and attitudes in college students. Methods: A student-faculty partnership administered a cross-sectional survey to undergraduate students (N 1/4 339) in 2019. Results: 49.8% of students reported using ENDS or vaping in the past 30 days. 48.9% of students who vaped reported vaping more than one substance in the past 30 days. The most commonly vaped substances were cannabis (34.9%), nicotine (26.7%), and flavor (19.2%). Reasons for initiating ENDS use were social (64.8%), for the high (40.8%), and for the flavor (32.4%). Both users and non-users believed ENDS were harmful and favored regulation. Conclusions: Young people who use ENDS commonly vape more than one substance; a critical finding in light of the current vaping lung injury epidemic. The importance of social reasons for initiating ENDS and broad support for regulation suggest jurisdictions consider regulation to reduce ENDS use in young adults.