As the field has moved toward defining and assessing the competencies needed by health-service psychologists, the importance of integrating ethics into education, training, and supervision has become increasingly clear. This introduction to the special section, Ethical Issues in Training and Supervision, begins with a brief review of the APA's Ethical Principles of Psychologists and Code of Conduct (Ethics Code; APA, 2010) and recent developments in the profession. The 12 articles in this section illustrate the current breadth of ethics in education and training within health-service psychology, representing a wide variety of approaches from the conceptual (including a paradigm shift from a more individualistic approach to a communitarian model) to the practical and the more empirical. Taken together, they both advance the literature and underscore the need for considerable future research. While the conceptual and practical articles challenge the profession to develop best practices, they are as yet unsupported by empirical study. Most of the studies in this section rely on Internet surveys, in which the demographics of the respondents may be skewed, and the response rate is generally unknown or too low to produce significant results. While ethical issues in doctoral, practicum, and internship programs are represented, postdoctoral programs are missing. The introduction to the special section concludes by offering recommendations including continuing to develop the evidence base in education and training, encouraging staff from practicum, internship, and postdoctoral programs to collaborate with faculty members in developing research in this area, and broadening competency lists to include teaching and administration.