Objective: We sought to assess sex differences in clinical presentation, management and outcome in emergency department (ED) patients with chest pain, and to measure the association between female sex and coronary angiography within 30 days. Methods: We conducted a prospective cohort study in an urban academic ED between Jul. 1, 2007, and Apr. 1, 2008. We enrolled patients over 24 years of age with chest pain and possible acute coronary syndrome (ACS). Results: Among the 970 included patients, 386 (39.8%) were female. Compared with men, women had a lower prevalence of known coronary artery disease (21.0% v. 34.2%, p < 0.001) and a lower frequency of typical pain (37.1% v. 45.7%, p = 0.01). Clinicians classified a greater proportion of women as having a low (< 10%) pretest probability for ACS (85.0% v. 76.4%, p = 0.001). Despite similar rates of electrocardiography, troponin T and stress testing between sexes, there was a lower rate of acute myocardial infarction (AMI) (4.7% v. 8.4%, p = 0.03) and positive stress test results (4.4% v. 7.9%, p = 0.03) in women. Women were less frequently referred for coronary angiography (9.3% v. 18.9%, p < 0.001). The adjusted association between female sex and coronary angiography was not significant (odds ratio 0.63, 95% confidence interval 0.37-1.10). Conclusion: Women had a lower rate of AMI and a lower rate of positive stress test results despite similar rates of testing between sexes. Although women were less frequently referred for coronary angiography, these data suggest that sex differences in management were likely appropriate for the probability of disease. © 2010 Canadian Association of Emergency Physicians.