We created EMROC to fill this crucial gap: to be able to successfully identify and enroll emergency department (ED) patients with acute disease. The majority of hospital admissions originate in the ED. Yet inadequate infrastructure dedicated to identifying patients early in their clinical course, along with poor communication or collaboration with other subspecialists, continue to be major factors hindering early enrollment. Our group has a thorough understanding of the ED environment, as well as intimate knowledge of sites and investigators with prior successful track records in observational and therapeutic clinical trials. Appropriate site selection is critical to successful patient enrollment. We understand the differences at each site and how these hurdles can be overcome.