On April 15, 2013, at approximately 2:50 pm, 2 explosions detonated near the finish line of the 2013 Boston Marathon. This incident happened at 4 hours and 9 minutes into the race, just after the elite runners had completed the race and at the peak of runner volume. Three people were killed and hundreds were injured during this horrific event, representing one of the most complex medical and forensic disasters in US history. The numbers of wounded and the resulting medical response in this event involved more than 8 major hospitals, each receiving an average of 20 or more patients. Injuries sustained included lower extremity and blast trauma involving complex medical interventions.

Several individuals from the Boston University School of Medicine Master of Science in Healthcare Emergency Management (BU HEM) degree program were either on the scene or involved in this event. Jonathan Hartenbaum (BU HEM '14), an intern at the Massachusetts Emergency Management Agency noted, “I was part of the design and facilitation team for the 2013 Boston Marathon preparedness table top exercise that was conducted in March 2013. I was able to see the perception versus the reality of the disaster response bombings. I am actively involved in supporting the preparation of the after action report.” Brent Hamula (BU HEM '14), the Boston Marathon Medical Supplies and Operations coordinator, was onsite at the marathon's finish line at Medical Tent A. He reported that “after the bombs went off we immediately began the process for triaging and transporting victims to local hospitals.” Finally, Greg Bond (BU HEM '12), a Boston Emergency Medical Services paramedic, reported that “I was on shift and dispatched to the scene to perform patient triage and transport to local hospitals.”

From what was observed at the time of the initial triage and the transportation to nearby medical facilities, and as noted by the hospitals involved, it was apparent that Boston had made significant efforts in preplanning and preparedness activities. In advance of the marathon, as standard practice, the State Emergency Operations Center and Medical Intelligence Center were already activated, and a unified command center had been established near the finish line. Several reports made by local hospitals and other officials noted that ongoing emergency preparedness planning, exercises, and drills made a clear difference in the speed and precision of the response to this incident.