Chapter 4 details the second session of the treatment program, including a discussion about common reactions to trauma (fear and anxiety, reexperiencing the trauma, increased arousal, avoidance, anger, guilt, grief and depression, negative self-image, suffering relationships, and alcohol or drug use), examples of in vivo exposure, an introduction to Subjective Units of Discomfort (SUDS), in vivo hierarchy construction, safety considerations, in vivo assignments, and the model of gradual in vivo exposure.