PROJECT SUMMARY/ABSTRACT Cigarette smoking remains the leading preventable cause of morbidity and mortality in the United States. Developing effective cessation interventions remains a public health priority, and mHealth offers the opportunity to reduce barriers to dissemination and implementation of cessation treatment. This project will test the emerging technology of augmented reality (AR) to enhance smoking cessation among individuals who contact the Tobacco Free Florida quitline for treatment services. AR inserts virtual objects into the real-world environment as viewed on a screen (e.g., smartphone). Cue-exposure treatments have demonstrated efficacy for decreasing tobacco craving in the laboratory, but these effects do not appear to generalize well beyond the extinction setting. This post-extinction “renewal effect” has been demonstrated in both animal and human studies. With the emergence of AR technology, it is now possible to conduct extinction trials across multiple environments throughout smokers’ own real-world smoking settings. The potential to extend the effects of cue- exposure to naturalistic settings offers the opportunity for an innovative and scalable cessation treatment that can be administered remotely. With funding from an R34 treatment development grant, the research team has already developed an app with the basic AR platform. Importantly, we have tested the app in controlled experiments and found that the AR stimuli satisfied the key criterion for extinction cues in that they: (a) elicited substantial cue-reactivity, comparable to in vivo cues and that (b) repeated exposure to the cues reduced craving (i.e., extinction). The primary goal of the proposed project is to extend this initial work by adapting the app for clinical use, with the objective of testing the efficacy of AR when combined with quitline treatment, while also considering key questions relevant to future implementation. Aim 1 will expand the app to be an engaging and user-friendly treatment tool for smokers, and to coordinate all referral procedures between the study team and the Tobacco Free Florida quitline. Aim 2 will recruit participants from the Tobacco Free Florida quitline and randomize individuals either to receive quitline services only or receive quitline services plus the AR app. The primary outcome is biochemically-confirmed tobacco abstinence at 6 months post-enrollment. Aim 3 will evaluate treatment implementation questions to guide future quitline adoption. If the AR app proves to be efficacious, it will be ready for dissemination and implementation through quitlines as well as other smoking cessation programs (e.g., traditional cessation counseling, text messaging interventions, other mobile cessation apps). This work has the potential to inform a range of existing treatments not only for tobacco dependence, but also for other substance use disorders and mental health conditions that are maintained by principles of conditioning.