Urie Bronfenbrenner

Urie Bronfenbrenner is the Jacob Gould Sherman Professor of Human Development and Family Studies and Psychology at Cornell University and was one of the founders of Head Start. Bronfenbrenner was born in Moscow and came to the United States when he was 6 years old. He received his bachelor’s degree from Cornell University in 1938, a master’s degree in developmental psychology from Harvard in 1940, and a PhD from the University of Michigan in 1942. Bronfenbrenner served as a military psychologist during World War II and an assistant professor at the University of Michigan from 1946 to 1948. He moved to his present location at Cornell in 1948.

As a child, Bronfenbrenner’s father, who was a neuropathologist, often pointed out the interdependence between living organisms and their surroundings. These concrete examples expanded into theories about the ecology of human development, developing substance during cross-cultural field research, which Bronfenbrenner has conducted in Europe, the U.S.S.R., Israel, China, and elsewhere. Bronfenbrenner realized that the developmental process varies by place and time and that public policy affects the development of human beings by determining the conditions of their lives.

Bronfenbrenner is most famous for creating a major theory of human development called the Ecology of Human Development. He conceived the human environment as consisting of a set of nested structures consisting of the microsystem, the mesosystem, the exosystem, and the macrosystem.

Bronfenbrenner defined development as a lasting change in the way a person perceives and deals with the environment, and a child is viewed as a growing, dynamic entity that progressively moves into and restructures the milieu in which it resides. The environment also exerts its influence, requiring a process of reciprocity between person and environment.

Later,  Bronfenbrenner  and  Ceci  (1994)  extended this theory to behavioral genetics. They recommended that explicit measures of the environment in systems terms should be incorporated, as well as proposing the existence of empirically assessable mechanisms, proximal processes through which genetic potentials for effective psychological functioning are actualized. They hypothesized that when proximal processes are weak, genetically based potentials for effective psychological functioning remain relatively unrealized, and as proximal processes increase in magnitude, potentials become actualized to a progressively greater extent.

Bronfenbrenner’s contributions have resulted in honors and awards on an international scale. He has been awarded six honorary degrees, invited to contribute to two Presidential Task Forces, and has been honored by the American Psychological Association for “Lifetime Contribution to Developmental Psychology in the Service of Science and Society.”


  1. Bronfenbrenner, (n.d.). Personal Web site. Retrieved, from http://www.people.cornell.edu/pages/ub11/
  2. Bronfenbrenner, (1970). Two worlds of childhood: U.S. and U.S.S.R. New York: Russell Sage Foundation.
  3. Bronfenbrenner, (1979). The ecology of human development: Experiments by nature and design. Cambridge, MA: Harvard University Press.
  4. Bronfenbrenner, U., & Ceci, S. J. (1994). Nature-nurture reconceptualized: A bio-ecological Psychological Review, 101, 568–586.