The Chicago School of Sociology emerged in the early 20th century at the University of Chicago. It focused on urban sociology and the study of social behavior in cities. Researchers emphasized the importance of the social environment in shaping individual actions and community dynamics, using qualitative methods like ethnography and participant observation. Key figures, such as Robert E. Park and Ernest W. Burgess, contributed to theories like the concentric zone model, which explains urban social structures. The Chicago School's work laid the foundation for modern sociology, influencing various fields, including criminology and social psychology.