Traditionally, the autopsy is viewed as the ultimate quality assurance indicator in clinical medicine, yet very few clinical departments actually incorporate autopsy results in their formal quality assurance plans. Consequently, to investigate how autopsy results can be included on our emergency department plan, the clinical and autopsy diagnoses of 244 patients were reviewed retrospectively and compared to identify conditions that were unapparent or misdiagnosed at the time of death. The study period was from January 1984 through June 1988. The average yearly ED census was 33,266. Differences between clinical and autopsy diagnoses were categorized as class 1, 2, 3, or 4 findings. Major unexpected findings (classes 1 and 2) were found in ten patients (4%); the most common missed diagnoses were aortic dissection 3 (1.2%) and pulmonary embolus 2 (0.8%). Minor unexpected findings (classes 3 and 4) were discovered in 14 patients (5.8%). The results clearly identify unexpected findings and point to the need for more aggressive evaluations of certain conditions. Systematic review of autopsy data as presented has led to meaningful changes and delivery of care to emergency patients. Autopsies are a vital source of outcome-based information that should be part of every ED's quality assurance and risk management plan.