PROJECT SUMMARY Opioid-related overdose deaths continue to climb at alarming rates – greater than 200% since 2000. Emerging adults (individuals aged 18-25 years old) are a key demographic in the opioid epidemic, and especially important to engage in treatment, as they account for increasingly high absolute and relative rates of fatal opioid overdoses. Emerging adulthood is a distinct developmental stage and so these treatment engagement efforts should be developmentally tailored. This application describes a 5-year patient-oriented mentored research and training plan to develop a behavioral intervention focused on engagement of high risk emerging adults to treatment after they present to the emergency department with a nonfatal overdose. The proposed intervention model is based on a motivational intervention to reduce overdose risk by improving self-efficacy in adults who have a history of recent nonmedical use of opioid analgesics. My career goal is to become an independent clinician investigator with an expertise in behavioral intervention development and testing for emerging adults with opioid use disorders. The specific aims of this application are to 1) quantify the time to addiction treatment or recurrent overdose for emerging adults who experience a nonfatal overdose, 2) use qualitative methods to inform intervention development for emerging adults who experience a nonfatal overdose, and 3) conduct a pilot trial to determine feasibility and logistics of the intervention. My educational objectives are to learn: 1) behavioral intervention development, 2) science of behavior change in emerging adults, and 3) clinical trial design. I have identified a well-respected mentoring team and a supportive environment to help me achieve my goals. The results from this work will position me to submit a R01 grant to conduct a fully-powered efficacy trial of an intervention to reduce overdose risk behaviors and increase treatment engagement among emerging adults with non-fatal overdose.