"Lessons Learned" is a series of publications that are a brief recounting of actual school emergencies and crises. This "Lessons Learned" issue focuses on an active shooter situation that escalated to a hostage situation that required multiple law enforcement agencies and other first responders and agencies to coordinate response and recovery efforts. The report illustrates the importance of establishing the functions outlined in the incident command (IC) structure at the beginning of the incident. Each function within the IC structure is linked to a rapid and effective response and also establishes the processes for recovery to begin before the incident is resolved. Partnerships are vital: the school alone cannot manage all aspects of the response and recovery. Working with first responders, mental health agencies and the community helped the school district develop strategies that will support students, staff and families. Based on the incident, educators, first responders, mental health agencies and parents engaged in dynamic discussions that explored a wide variety of options to ensure that district schools provide a safe environment that fosters academic learning and social development of the students. The lessons provided give other districts suggestions for creating an all-hazards emergency management plan in conjunction with partners. (Contains 2 footnotes and 1 figure.) [This publication was produced by the Emergency Response and Crisis Management (ERCM) Technical Assistance (TA) Center and the U.S. Department of Education's Office of Safe and Drug-Free Schools (OSDFS). For Volume 2, Issue 4 of this series, see ED504387.]