BACKGROUND AND AIMS: Increasing demand for inpatient endoscopic services results in performing more non-emergent endoscopic cases after-hours, which poses risks to patient safety and negatively impacts patient and provider satisfaction. This study sought to quantify the existing state using quality improvement (QI) methodology, design targeted interventions, and determine their effectiveness. METHODS: We conducted an existing state evaluation through a process map, time-series study, and caseload analysis from 7/2017-12/2018. Using end-of-workday (EOW) as a proxy for patient/provider dissatisfaction and risk for patient safety events, we performed a prospective evaluation of a staged interdisciplinary multimodal intervention aimed to decrease the proportion of days with EOW after 7PM, decrease the proportion of cases begun after 5PM, and decrease EOW variability. The post-intervention period was 6/2019-2/2020. RESULTS: Based on existing state analyses, we implemented a series of targeted interventions: (1) provider workflow tips, (2) expedited transport for select patients, (3) pathway to reschedule appropriate cases to outpatient endoscopy, and (4) increased staffing for high caseload days through resource pooling. The proportion of days with EOW after 7PM decreased from 42.4% to 29.3% (caseload-adjusted odds ratio of 0.39, p< 0.001). Despite increased caseload, cases begun after 5PM decreased from 17.5% to 14.2% (OR 0.75, p = 0.009). EOW SD decreased from 2:20 hours to 1:36 hours. CONCLUSIONS: The multimodal intervention reduced days with EOW after 7PM and the proportion of cases begun after 5PM, despite increased caseload. This study shows how applying research methods to implement QI interventions successfully decreases late inpatient endoscopic cases.