7Offering the wisdom of practitioners from the military, law enforcement, fire and rescue, as well as prominent scholars this guide integrates theory and research with practical experience to help the reader prepare for the unique psychological, social, and physical challenges of leading in dangerous contexts. Whether a young soldier preparing for war, seasoned combat commander, SWAT team leader, EMT supervisor, law enforcement patrol unit leader, or fire department lieutenant, those involved in life-and-death situations face common challenges, and the authors draw on their own experiences and that of others to help first responders effectively function in dangerous environments.