Elizabeth was awarded a grant to collect pilot data on vaporization of cannabis oil using ecological momentary assessment titled Marijuana Vaporization: An Ecological Momentary Assessment Pilot Study. Vaporization of marijuana, or “vaping,” is rapidly becoming a prevalent mode of administration in the wake of legal and political shifts surrounding marijuana. Vaping prevalence is expected to continue to rise as device availability and popularity grows, and the market profitability will be prioritized without consideration of public health implications, as seen with electronic cigarettes. Unfortunately, several basic questions about vaping remain unanswered including: when, where, and why do individuals vape, how much do they consume, and for whom is vaping most problematic? This pilot study aims to utilize novel ecological momentary assessment methodologies to examine vaping in “real time” from users in their natural environment during a 30-day monitoring period. The study will use an observational within-subjects design of 15 frequent marijuana users who have experience vaping marijuana oil. Participants will be provided with a cutting-edge, handheld vaporizer that wirelessly records vaping consumption data in real-time that syncs with a mobile-application that can capture what happens in-the-moment when individuals vape. The following primary specific aims are proposed: (1) Examine frequency of marijuana vaping within- and across-days; (2) Examine quantity of marijuana consumption while vaping; (3) Examine where vaping occurs; and (4) Examine precipitants to use, including situational, cognitive, and emotional factors. An exploratory aim is to examine individual differences that influence vaping , including age, medical user status, and presence of psychopathology. This funding will facilitate innovative and significant research and will provide the necessary pilot data for an NIH R01 grant.