Summary: Providing a thorough discussion of the principles essential for a psychologist's ethical conduct toward human participants during the course of research, this guide enables students and researchers to assure that human participants in research are protected from psychological or physical harm. Based on the APA Ethical Principles for Psychologists, Principle 9, this publication reviews necessary steps to insure that participants understand the research procedure ...show more, the implications of their consent to participate, and their freedom to decline or withdraw. Other information deals with participation debriefing and protection from disclosure of individual results to unauthorized persons. Particular emphasis is placed on special precautions for vulnerable populations and issues involved in research requiring concealment or deception. This book outlines the responsibilities of researchers for the proper conduct of research; proscribes relationships between the researchers, their associates, and their sponsors; and sets out guidelines for relationships among researchers and the participants in research projects.