Nursing practice in forensic psychiatry opens new horizons in nursing. This complex, professional, nursing practice involves the coupling of two contradictory socioprofessional mandates: to punish and to provide care. The purpose of this chapter is to present nursing practice in a disciplinary setting as a problem of governance. A Foucauldian perspective allows us to understand the way forensic psychiatric nursing is involved in the governance of mentally ill criminals through a vast array of power techniques (sovereign, disciplinary, and pastoral), which posit nurses as subjects of power. These nurses are also objects of power in that nursing practice is constrained by formal and informal regulations of the forensic psychiatry context. As an object of governmental technologies, the nursing staff becomes the body onto which a process of conforming to the customs of the forensic psychiatric milieu is dictated and inscribed.