Urie Bronfenbrenner, 88, a Cornell University psychologist who pioneered an interdisciplinary approach to the study of child development and helped create the federal Head Start program, died Sept. 25 at his home in Ithaca, N.Y. He had complications from diabetes.

The Russian-born Bronfenbrenner was credited with creating the interdisciplinary field of human ecology and was widely regarded as one of the world's leading scholars in developmental psychology and child rearing.

Before Dr. Bronfenbrenner, child psychologists studied the child, sociologists examined the family, anthropologists the society, economists the economic framework of the times and political scientists the governing structure.

"Urie was the quintessential person for spurring psychologists to look up and realize that interpersonal relationships, even the smallest level of the child and the parent-child relationship, did not exist in a social vacuum," said Melvin L. Kohn, a professor of sociology at Johns Hopkins University who studied under Dr. Bronfenbrenner.

Earlier in his career, Dr. Bronfenbrenner helped spur the creation of Head Start, the federal child development program for low-income children that has served millions since 1965.

According to an account on the American Psychological Association's Web site, Dr. Bronfenbrenner was on a Head Start planning committee appointed by R. Sargent Shriver, director of President Lyndon B. Johnson's anti-poverty efforts. Dr. Bronfenbrenner persuaded his colleagues to include the family and community in Head Start to better help poor children.

In his later years, Dr. Bronfenbrenner warned that the process that makes human beings human was breaking down as trends in American society produced chaos in the lives of children.

"The hectic pace of modern life poses a threat to our children second only to poverty and unemployment," he said.

He was the author, co-author or editor of 14 books and more than 300 articles and chapters. The American Psychological Association gives an annual award in his name for contributions to developmental psychology.

At his death, Dr. Bronfenbrenner was the Jacob Gould Sherman professor emeritus of human development and family studies and of psychology at Cornell.

Born in Moscow in 1917, Dr. Bronfenbrenner came to the United States at age 6. He received a bachelor's degree from Cornell in 1938, a master's from Harvard University and a doctorate from the University of Michigan. He served in the Army as a psychologist before joining the Cornell faculty in 1948.

Survivors include his wife, Liese, and six children.

Urie Bronfenbrenner helped create the Head Start program.