This comprehensive text explores the entire range of research methodologies in psychology, using a carefully constructed programmatic approach to introduce topics and systematically build on the earlier presentations. This text emphasizes research concepts, as well as specific, technical research strategies, to help students develop an understanding of the underlying rational-empirical processes of science and to gain specific research skills. It provides clearly written explanations of concepts and numerous examples drawn from all areas of psychology to enable students to develop sophisticated understanding of the research process.