Effectiv. e management of post-operative pain improves the condition of patients and reduces their hospital stay. This, in turn, has an impact on caregivers, professionals, and institutions and, as such, is considered a primary indicator of quality. The aim of this project was to improve the assessment and management of post-surgical pain in thoracic surgery patients. This implementation project was conducted in a thoracic surgery unit of a tertiary hospital in Spain. The project was guided by the JBI Evidence Implementation Framework, which is grounded in an audit, feedback, and re-audit strategy. A baseline audit was conducted with 44 patients, and barriers to best practice were identified. Strategies were then implemented to improve the assessment and management of post-operative pain. Three follow-up audits were performed using nine audit criteria with 34, 40, and 46 patients, respectively. The baseline audit revealed poor compliance with best practices. After implementing strategies to address areas of non-compliance, health education for patients and caregivers improved up to 80%, while the measurement of pain upon admission and post-surgery rose to 91%. However, patients undergoing pre-operative assessment to guide their post-operative pain management at hospital discharge remained below 50%. Using a methodology to implement best practices, together with clinical audits, improved compliance with the use of validated scales to assess and manage pain. A multidisciplinary approach improves the quality of care received by patients and contributes to their recovery. http://links.lww.com/IJEBH/A240.