Frontline crisis response is challenging. Emergency responders, soldiers, and humanitarian aid workers all operate at the frontlines of threatening, uncertain crisis situations on a daily basis. Under intense pressure, they need to make a range of difficult decisions: to follow preexisting plans or improvise; to abide by top-down instructions or take discretionary actions; to get emotionally involved or keep a rational distance? These dilemmas define their work but, until now, have not been subjected to systematic investigation. This book conducts in-depth studies of eleven such dilemmas by integrating a wide array of research findings on crisis response operations. The comprehensive overview of crisis response research shows how frontline responders deal with these dilemmas amidst the chaos of crises and forms the basis for the formulation of a theory of frontline crisis response. As such, this book will undoubtedly help to understand, evaluate, and advance crisis response operations.