Director of the Developmental Core, is a Professor of Sociology. He is one of the first researchers to study contemporary Chinese migration patterns in the age of market transition in China. For nearly two decades, with support from the Rockefeller Foundation, the NIH, NSF, Spencer Foundation, and CCK Foundation, he has been engaged in a research program to examine the massive flow of internal migrants in China. He has also focused on international migration from China to the United States. With support from NIH, NSF, and the Ford Foundation, he has completed a major data collection project and has been analyzing data from this project. A more recent project, sponsored by the Russell Sage Foundation, examines new settlement patterns of low skilled Chinese immigrants in the U.S.