Focused assessment with sonography in trauma (FAST) has been extensively utilized and studied in blunt and penetrating trauma for the past 3 decades. Prior to FAST, invasive procedures such as diagnostic peritoneal lavage and exploratory laparotomy were commonly utilized to diagnose intraabdominal injury. Today the FAST examination has evolved into a more comprehensive study of the abdomen, heart, chest, and inferior vena cava, and many variations in technique, protocols, and interpretation exist. Trauma management strategies such as laparotomy, laparoscopy, endoscopy, computed tomographic angiography, angiographic intervention, serial imaging, and clinical observation have also changed over the years. This state of the art review will discuss the evolution of the FAST examination to its current state in 2017 and evaluate its evolving role in the acute management of the trauma patient. The authors also report on the utility of FAST in special patient populations, such as pediatric and pregnant trauma patients, and the potential for future research, applications, and portions of this examination that may be applicable to radiology-based practice. © RSNA, 2017 Online supplemental material is available for this article.