In this survey of the research on psychological approaches to play, the author outlines its various focuses on the similarities and differences in the thinking and behavior of individuals and groups in relation to play and on the environmental factors that influence these. She notes that although psychologists often use standard experimental research methods to study play, they also conduct studies based on direct observations, interviews, and other qualitative activities. These researchers, she notes, have been particularly interested in testing theories of play, developing systems to explain playful behavior, and understanding how play influences education and child rearing and their effect on development and learning. The author also surveys researchers from other disciplines, such as philosophy, ethology, anthropology, linguistics, and education, who have studied the psychology of play. They, she concludes, often employ research methods similar to those used by psychologists, and thus their work, too, has contributed to a psychological understanding of the thinking and behavior related to play and the environments that encourage it.