EMS prenotification was associated with increased likelihood of alteplase treatment within 3 hours (82.8% versus 79.2%), shorter door-to-imaging times (26 minutes versus 31 minutes), shorter DTN times (78 minutes versus 80 minutes), and shorter symptom onset-to-needle times (141 minutes versus See Table I in online Data Supplement 1. 1.1. Prehospital Systems COR LOE New, Revised, or Unchanged Public health leaders, along with medical professionals and others, should design and implement public education programs focused on stroke systems and the need to seek emergency care (by calling 9-1-1) in a rapid manner. These programs should be sustained over time and designed to reach racially/ ethnically, age, and sex diverse populations. I B-NR Recommendation revised from 2013 Stroke Systems of Care. COR and LOE added. Such educational programs should be designed to specifically target the public, physicians, hospital personnel, and emergency medical services (EMS) personnel to increase use of the 9-1-1 EMS system, to decrease stroke onset to emergency department (ED) arrival times, and to increase timely use of thrombolysis and thrombectomy. I C-EO New recommendation. Early stroke symptom recognition is essential for seeking timely care. Unfortunately, knowledge of stroke warning signs and risk factors in the United States remains poor. Blacks and Hispanics particularly have lower stroke awareness than the general population and are at increased risk of prehospital delays in seeking care.20 These factors may contribute to the disparities in stroke outcomes. Available evidence suggests that public awareness interventions are variably effective by age, sex, and racial/ethnic minority status.21 Thus, stroke education campaigns should be designed in a targeted manner to optimize their effectiveness.21 See Tables I and II in online Data Supplement 1. Activation of the 9-1-1 system by patients or other members of the public is strongly recommended. 