I am currenlty a professor of sociology at the University of Pennsylvania. My research focuses on African and African Diaspora populations. I have published several articles, two books and edited several volumes of journals and books on my research. My current research continues to focus on these themes. I am working with my collaborators in the African Census Analysis Project to produce a number of volumes on the General Demography of Africa. The first volume has been completed with several other volumes currently being prepared. I am also working on a long term project on human migration and difference. I have been working on this latter project for a few years and will continue to work on it for several more years before it is finished.