Background: Accurate TNM staging of malignancy is essential to quality care of cancer patients but maintaining consistent documentation of appropriate staging remains a challenge. We identified documentation of TNM staging at our institution to be below target levels. We sought to improve documentation of staging in all patients at our cancer center with a diagnosis of malignancy by implementing both automated and manual reminders through our electronic medical record (EMR) software (Epic), as well as by using team accountability. Methods: We defined an expectation that all patients seen at UC San Diego Moores Cancer Center with a billing diagnosis of malignancy would have TNM staging documented in the EMR within 1 month of their initial visit. The project started in 1/2016, with a phased rollout to individual teams, including education and outreach prior to the start of performance tracking. We used the AJCC staging module in Epic and focused on all new patient visits with a billing diagnosis of malignancy. Providers were asked to add this diagnosis to the problem list and then document the stage using the AJCC staging module in EPIC. We tracked compliance by individual provider and by team and emailed performance reports to all providers on a monthly basis. To facilitate compliance, we initiated automatic Epic messages to providers for an unstaged cancer diagnosis on the problem list and followed up with a personal email from administrative staff if documentation was not completed in a timely manner. Results: At the initiation of this project, there was no standardized documentation of cancer staging. The project was phased in with the skin cancer and head and neck cancers teams in phase I. Compliance in the initial month of measurement was 28%. Within 3 months of implementation of the project, compliance was over 50%, and within 27 months, over 90%. Compliance has remained > 90% since. For 3/2020, 368 patients were eligible for staging and 98% were staged within a month of their visit. Conclusions: Documentation of TNM staging of malignancy was significantly improved by both automated and personal reminders with a vital component of team accountability. Further efforts to improve the current practice and culture of documentation for diagnosed cancer patients remains a crucial aspect of quality and safety.