The volumes of this work consist of nineteen chapters. Seventeen were written by psychologists expert in a particular branch of our field. For this reason, the book as a whole is not organized chronologically, as reflected in our title Topics in the History of Psychology. The first chapter in each of the volumes are the editors' attempts to remedy this deficiency. The first volume covers the areas of conditioning and learning, human learning and memory, sensory and perceptual processes, comparative psychology, and physiological psychology. Volume 2 covers the history of behavioral genetics, psychological testing, developmental psychology, drives and motives, sleep and dreaming, psychotherapy, psychopathology, personality theory, and social psychology.