We review guidelines for providing supervision for trainees and employees, an expected part of the job for many psychologists, many of whom carry out their supervisory duties with only a cursory awareness of the ethical and legal pitfalls that may accrue. The guidelines are drawn from ethical principles, other documents promulgated by various sectors of professional psychology, and relevant legal cases. Specific suggestions are given for supervisors and training institutions to ensure appropriate supervision. The incorporation of training in supervision in all doctoral programs in professional psychology is recommended.Clinical supervision has become an area of intense interest in recent years. This interest has been reflected in reviews of ideal supervisor characteristics (Carifio & Hess, 1987), empirical studies of psychotherapy supervision (Lambert & Arnold, 1987), development of models of supervision (e.g., Stoltenberg & Delworth, 1987;Worthington, 1987), and evaluations of supervisees' perceptions of supervisory practices (Allen, Szollos, & Williams, 1986). These and similar articles have focused primarily on the process and content of supervision.Supervisors also need to be familiar with ethical and legal aspects of supervision that transcend their theoretical orientations and teaching skills (Bent & Cannon, 1987). The ethical issues include supervisor qualifications, duties and responsibilities of supervisors, dual relationships, client consent, and thirdparty payments. The legal liability of supervisors extends into such areas as direct and vicarious liability, confidentiality and the duty to protect, and standard of care.In this article we discuss the ethical and legal aspects of the supervision of trainees in psychology, such as what occurs in practica, internships, and postdoctoral work before licensure. We provide a generic coverage of the ethical and legal issues as they apply to all theories or models of supervision. We do not detail how these principles may be played out in unique ways in specific theoretical approaches to training (e.g., supervision in analysis), in supervision for ongoing enhancement of skills by