Critical incidents occur within a context of chronic trauma to an individual or group. The Cumulative Traumatic Stress model is proposed to respond to these incidents. Cumulative vicarious trauma refers to a set of critical incidents of sufficient intensity and frequency to result in chronic, individual, delayed stress symptoms among individual service providers and disintegrating effects on service teams. Professionals in close contact with clients who experience ongoing crises and traumas often develop posttraumatic symptoms, and their exposure to several critical incidents can have a cumulative effect. Work- related effects of cumulative vicarious trauma include chronic symptoms commonly associated with delayed stress response. Cumulative traumatic stress (CTS) affects more than the individual; when it is a work-related phenomenon, CTS is likely to affect all team members. Goals of the Cumulative Traumatic Stress Debriefing (CTSD), a group intervention, are to address and moderate traumatic stress symptoms and build group cohesiveness among participants. The CTSD protocol follows specific phases that encompass incidents, complications, reactions, coping strategies, and planning phases.