Edited by Prof.s Carmen Martínez Capdevila and Enrique J. Martínez Pérez, this book  gathers the papers submitted to the Symposium "Challenfes for the European Union External Action", held in Valladolid 9 and 10 june 2016, as part of the Jean Monnet Project “EU Law between Universalism and Fragmentation: Exploring the Challenge of Promoting EU Values Beyond its Borders”, granted to the AEPDIRI.