Visits to emergency departmentsEmergency departments (ED) are increasing, and overcrowding has become a serious problem for hospitals, patients, physicians, and clinical staff. In this case study, a cross-functional team representing the ED, inpatient floors, and units including clinical, ancillary support staff, and nonclinical members applied LeanLean Six SigmaLean Six Sigma methodologies and tools to drastically reduce the patient length of stayLength of stay (LOS) and the percent of patients Left Without Being SeenLeft without being seen. There was a 31% reduction in LOS which is closely tied to patient satisfactionPatient satisfaction. The percent of Left Without Being SeenLeft without being seen was reduced from 6.5 to 0.3%. The door-to-doctor time was reduced by 78% to an average of 23 min. Patient SatisfactionPatient satisfaction scores increased by 24% to 89.9% which placed this EDs department in the top 1% of EDs nationally.