Incarcerated teens are at risk for a wide variety of injuries and illnesses. Careful screening and follow-up assures the teen will medically benefit from incarceration and improve their chances of rehabilitation. This chapter is divided into four sections: medical problems that may predispose to delinquent behavior; medical illness and injury likely to result from delinquent behavior; health concerns for all adolescents; and health maintenance issues. Governmental agencies advocate for appropriate research and have built-in safeguards for all research involving prisoners, including stipulating the types of permissible research. Medical personnel at large facilities should be involved as primary investigators or as collaborators with other investigators. Conducting sound ethical, targeted research will greatly aid progress in reducing the burden of crime and illnesses for juvenile delinquents. Cooperation is necessary among medical, custody, and judicial personnel to obtain funding for studies and to facilitate the conduct of research.