Introduction: In 2016, the Emergency Department (ED) Return Visit Quality Program (RVQP) was developed to promote a culture of quality in Ontario EDs, by mandating large-volume EDs to audit charts of patients who had a return visit leading to hospital admission (RV). This program provides an opportunity to identify possible adverse events (AEs) and quality issues, which can then be addressed to improve patient care. Methods: The RVQP requires EDs to audit a set number of 72-hour RVs for potential AEs/quality issues, as well as all 7-day RVs for one of three key paired sentinel diagnoses (acute myocardial infarction, subarachnoid hemorrhage, and pediatric sepsis). Submitted audits and their AEs/quality issues were analyzed by a team of emergency physicians with quality improvement (QI) expertise, and qualitative metrics were derived. Using the general inductive method, we conducted a qualitative analysis with Health Quality Ontario (HQO), and HQO completed an independent analysis of the submitted narrative reports. Our objective is to report on the qualitative and quantitative metrics of the program, and to explore emerging themes from the AEs/quality issues identified. Results: There were 36,304 72-hour RVs flagged, which represent 0.99% of all 3,672,708 ED visits in the province of Ontario for the 86 EDs participating in the first year of the program. Overall, 2,584 audits were conducted. For the audits involving all-cause 72-hour RVs, 571 (24%) of cases had AEs/quality issues identified. Of the 219 audits involving sentinel diagnoses, 107 (49%) audits identified AEs/quality issues. The qualitative analysis revealed 11 themes, which were classified into three groups : issues related to patient characteristics or actions (elder care, patient risk profile, left without being seen); issues related to actions or processes of the ED team (physician cognitive lapses, handover/communication, high risk medications, documentation, radiology, vital signs); and healthcare system issues (imaging/test availability, discharge planning). Over one hundred local QI projects were completed or planned as a result of the audits performed. Conclusion: The RVQP promotes a culture of quality by highlighting potential AEs and quality themes that can then be targeted to increase patient safety and quality of care in Ontario EDs. Numerous QI projects were undertaken in the first year of the program, and future efforts will monitor the completion and success of these. The program can be easily adapted in other jurisdictions.