The need for mental health professionals to become more aware of the forensic issues raised by their everyday functions is explored, together with an examination of the evolution of the field of forensic mental health and its function in society. Guidelines essential for the psychiatric-legal opinion are presented. Applications of the principles of forensic psychiatry are discussed, with emphasis on the standards for determining mental problems related to legal criteria and the identification of legal dangerousness. The insantiy defense, the issue of malingering, the mental health practitioner, and the significant features of mental health reports written for legal purposes are also examined. The case of Tarasoff v. Regents of the University of California is discussed, with emphasis on the implications of the decision and its implementation. Chapter reference lists, a table, a figure, and an index are supplied.