This chapter describes the range and timeline of typical reactions, approaches for screening, triage, and referral, preventing and managing psychological injuries, and integrated strategies to support disaster responders. Disasters and acts of terrorism produce a spectrum of common physiological, psychological, social, behavioral, emotional, cognitive, and spiritual reactions. An emerging incident management model for disaster mental and behavioral health is composed of three major components to enable a common operational picture for participating entities and jurisdictions. The components include community-based disaster systems of care, a common system for incident/event-specific rapid triage, and information technology for near-real-time data linkage. Psychological impact and resulting levels of psychiatric disorders may vary as a function of event characteristics, such as terrorism using weapons that can cause mass casualties and societal disruption. Using leadership, public messaging, and education greatly improves the mental and behavioral health of communities impacted by disasters and mass violence.