 He held the Swiss Chair in Mobility Studies during the Fall semester of 2009 as a visiting professor at the Institute of Social Anthropology at the University of Bern in Switzerland, and was a Visiting Research Professor in the Institute of Migration and Ethnic Studies at the University of Amsterdam in 2010.From 2000 to 2009, he was Assistant Professor of anthropology and Latino Studies at Columbia University.Prior to his time at Columbia, he served as a visiting professor at Stanford University (1997-1999).His research centers primarily on migration, borders, citizenship, and race.