Kelly Lytle Hernandez is associate professor in the UCLA Department of History and Associate Co-Director of the National Center for History in the Schools. Her research interests are in twentieth-century U.S. history with a concentration upon race, migration, and police and prison systems in the American West and U.S.-Mexico borderlands. Her book, MIGRA! A History of the U.S. Border Patrol (University of California Press, 2010) is the first book to tell the story of how and why the U.S. Border Patrol concentrates its resources upon policing unsanctioned immigration across the U.S>-Mexico border despite the many possible targets and strategies of U.S. migration control. Her current research focuses upon exploring the social world of incarceration in Los Angeles between 1876 and 1965.