The United States has one of the highest rates of incarceration in the world. Prisoners have high rates of mental health concerns, which affect their overall functioning and increase recidivism rates. Anxiety disorders and post-traumatic stress disorder have some of the highest rates of prevalence in corrections than in the community. These conditions are associated with significant comorbidity, risk of self-harm, and suicide. Although they do not fall under the purview of SMI, they are often unnoticed and underdiagnosed. In this chapter, we cover anxiety disorders in prisoners, their causes, prevention, and strategies for post-prison support.