Abstract. Objectives: Bedside ultrasound examination by emergency physicians (EPs) is being integrated into clinical emergency practice, yet minimum training requirements have not been well defined or evaluated. This study evaluated the accuracy of EP ultrasonography following a 16-hour introductory ultrasound course. Methods: In phase I of the study, a condensed 16-hour emergency ultrasound curriculum based on Society for Academic Emergency Medicine guidelines was administered to emergency medicine houseofficers, attending staff, medical students, and physician assistants over two days. Lectures with syllabus material were used to cover the following ultrasound topics in eight hours: basic physics, pelvis, right upper quadrant, renal, aorta, trauma, and echocardiography. In addition, each student received eight hours of hands-on ultrasound instruction over the two-day period. All participants in this curriculum received a standardized pretest and posttest that included 24 emergency ultrasound images for interpretation. These images included positive, negative, and nondiagnostic scans in each of the above clinical categories. In phase II of the study, ultrasound examinations performed by postgraduate-year-2 (PGY2) houseofficers over a ten-month period were examined and the standardized test was readministered. Results: In phase I, a total of 80 health professionals underwent standardized training and testing. The mean Ϯ SD pretest score was 15.6 Ϯ 4.2, 95% CI = 14.7 to 16.5 (65% of a maximum score of 24), and the mean Ϯ SD posttest score was 20.2 Ϯ 1.6, 95% CI = 19.8 to 20.6 (84%) (p < 0.05). In phase II, a total of 1,138 examinations were performed by 18 PGY2 houseofficers. Sensitivity was 92.4% (95% CI = 89% to 95%), specificity was 96.1% (95% CI = 94% to 98%), and overall accuracy was 94.6% (95% CI = 93% to 96%). The follow-up ultrasound written test showed continued good performance (20.7 Ϯ 1.2, 95% CI = 20.0 to 21.4). Conclusions: Emergency physicians can be taught focused ultrasonography with a high degree of accuracy, and a 16-hour course serves as a good introductory foundation.