Background: Little is known about the outcomes of adults with syncope seen in Canadian Emergency Departments (EDs). Objectives: We sought to determine the frequency, timing, and type of serious adverse outcomes occurring in these patients, and the proportion that occur outside the hospital. Methods: We conducted a health records review of syncope patients presenting to a tertiary care ED over an 18-month period. We included all patients older than 16 years of age who fulfilled the syncope definition (sudden transient loss of consciousness with spontaneous complete recovery), and excluded those with altered mental status, alcohol or illicit drug use, seizure, or trauma. We assessed for outcomes in the ED and after ED disposition. We also evaluated follow-up arrangements for patients discharged from the ED. Results: Of the total 87,508 patient visits, 505 (0.6%) were due to syncope. The mean age was 58.5 years (range 16-101 years), 70.1% arrived by ambulance, and 12.3% were admitted to the hospital. Five patients died: 2 in the ED, 1 as an inpatient, and 2 after discharge. Overall, there were 49 (9.7%) serious outcomes, with dysrhythmias being the most common (4.6%); 22 (4.4%) occurred in the ED, 15 (3.0%) in the hospital, and 12 (2.4%) outside the hospital. Eight serious outcomes occurred in patients discharged from the ED without any planned follow-up. Conclusion: Although syncope represented < 1% of all patient visits, morbidity was substantial, particularly in patients discharged from the ED. Future research should help clinicians identify syncope patients at high risk for serious outcomes. Copyright © 2013 Elsevier Inc. Printed in the USA. All rights reserved.