Psychologists who are members of their national society are bound by the rules of conduct of that society and are required to be licensed to practice by either a regulatory or other body. Core principles that psychologists should be aware of and which tend to form the framework of their associations or societies concern questions of competence, the advertising of services, confidentiality and record keeping, personal conduct and interpersonal relationship issues, the conduct of research, assessment, and the use of test results. Each of these areas is addressed in this chapter.