1. Assistant Professor, Department of Sociology, American University, Washington, DC.
2. Postdoctoral Fellow in Sociology, Harvard University.
3. Professor, Department of Sociology, University of Alberta.
4. Social Scientist, Africa Region, World Bank.
5. Professor, Department of Sociology, and Visiting Scholar, California Center for Population Research, University of California, Los Angeles.
6. Assistant Professor, Department of Health and Behavioral Sciences, University of Colorado Denver.