1 In 2017, 191 million opioid prescriptions were dispensed in the United States of which a 2 significant portion were prescribed for acute pain management following surgical encounters. In 3 addition, on average, 70% to 90% of prescribed opioid pills following surgery remain unused 4 and over 70% of surgery patients do not dispose of their unused opioids. Unused pills are a 5 common source of nonmedical use; 54% of people obtain their pills for nonmedical use through 6 friends or relatives and 35% through their healthcare provider. Nonmedical use of opioids can 7 lead to Adverse Drug Events (ADEs), and is frequently a pathway to the use of other, illicit, 8 drugs such as heroin. Our research team is currently funded by the National Institute on Drug 9 Abuse (NIDA) to develop methods for decreasing opioid prescribing in surgery, and through this 10 ongoing research we have identified that even after decreasing the number of pills prescribed a 11 large number of pills still go unused. Given the variation in individual patient use and the 12 provider's desire to provide adequate pain control to all of her patients, this will likely continue to 13 be the case for the foreseeable future. Furthermore, very few patients safely store their opioid 14 pills or dispose of them correctly, even when provided information on the importance and 15 methods for taking appropriate action. As we consider the next phase of improving our opioid 16 prescribing practices, decreasing the number of pills prescribed cannot be the end of our best 17 practices recommendations but rather the beginning. Effective prevention of harm caused by 18 prescription opioids requires patients to safely use pills; using only the minimum needed to 19 control pain, safely storing them, and appropriately disposing of unused pills after acute pain 20 treatment. 21 This study, Preventing Opioid Misuse through Safe Opioid Use Agreements 22 between Patients and Surgical Providers (PROMISE ME), will test the use of contractual 23 agreements to improve safe opioid use to prevent misuse and opioid-related harm. We will (1) 24 assess the barriers and facilitators to implementing opioid use agreements in the surgical 25 setting, (2) measure implementation effectiveness outcomes and provide real-time improvement 26 strategies while we (3) test the effectiveness of the intervention using a step-wedged cluster 27 randomized trial. The study will have a significant impact on prescription abuse as it directly 28 addresses the availability of excess prescription opioids within the community which is the 29 primary source of misuse and harm. We will disseminate the new knowledge generated from 30 this study throughout our 56-hospital learning collaborative