Description: Analysis of operating room efficiency at Houston Methodist The Woodlands Hospital (HMTW) in June 2019 revealed an opportunity for improvement in room turnover time. Turnover is measured from the time a patient leaves the operating suite, to the time (in minutes) the next patient enters the same suite. An observation was made that case carts containing supplies and instrumentation for each case were disorganized and often incomplete, requiring a significant amount of time to organize supplies and identify missing items. Observed variations in case cart preparation lead to ineffective utilization of time between cases, resulting in increased turnover time, and ultimately decreased Operating Room (OR) efficiency. Materials personnel, surgical technologists and nurses responsible for preparing case carts were interviewed for feedback on current process, including areas of concern and opportunities for improvement. Based on research conducted regarding OR efficiency and Lean strategies, an audit tool was developed to evaluate case carts for accuracy, completeness, and record the number of minutes required to prepare to open. Over a span of 4 months, volunteers were given the audit tools and instructed to directly observe and record the number of minutes needed to obtain the case cart from the sterile core, review the supplies in the case cart, and prepare to open. This observation and audit process was conducted in thirty cases across two service lines with heavy supply volumes, such as total joint and robotic procedures. Following evaluation of the audit tools, a new process was developed for standardizing case cart layout. Standardization included outlining where certain items are placed on every cart. Two color coded plastic bins were used to separate “hold” versus “open” items. Color coded visual signs were developed to quickly identify first case starts, regularly scheduled cases, and add-on cases within the sterile core. Following implementation, thirty audits were repeated utilizing volunteers in the same service lines and following the same time measurement process. Utilization of new strategies and tools developed decreased the number of minutes by 15-20% per case. A 15-20% decrease in the number of minutes per case spent on reviewing and organizing case cart supplies had a positive direct impact on OR efficiency. Project implementation also decreased overall turnover times and maximized physician operating time. Perioperative nursing implications include improved resource utilization, optimized staff workflow, and increased employee satisfaction. Once the process is further evaluated and refined, it can be implemented in other operating rooms with similar impact on turnover times.