This chapter describes the theory and practice of schema therapy (ST) in forensic settings, drawing primarily on work conducted with forensic mental health patients. Clinical studies and meta-analyses indicate that personality disorders (PDs) are highly prevalent in correctional settings. ST utilizes a number of techniques to change early maladaptive schemas, maladaptive coping responses, and schema modes. In ST for patients who present with less severe PDs, cognitive techniques are often used in the early stage of the therapy to help achieve more intellectual distance from early maladaptive schemas. A number of important modifications of ST are needed when working with more severe PD patients, such as those with antisocial, narcissistic, o...