Believing that an individual's development is strongly influenced by the way the person perceives his or her environment, Kurt Lewin had a strong influence on the theoretical foundations of social-emotional climate research. Lewin's theories may be compared with the following basic theoretical foundations of social climate research: symbolic interactionism; the environmental psychology of Wohlwill; Barker's ecological psychology; Brunswik's theory; the need-press-concept of Murray; Bronfenbrenner's ideas concerning topological regions; the concept of isomorphy; and the social learning theories of Rotter, Mischel, and Bandura. Most of these theories were influenced by Lewin's ideas concerning the importance of the subjective environment. In addition to theoretical contributions, Lewin also contributed empirical results, including his investigation of human behavior in different social emotional climates and his social research in factories. However, a big discrepancy exists between theory and practice in social-emotional climate research, especially with regard to the use of questionnaires and their inability to generate objective findings. (RM)