When we talk about migration, we assume the existence of borders. But what are borders? And should there be any? This is the topic of this episode with Bridget Anderson, Professor of Migration, Mobilities and Citizenship at the School of Sociology, Politics and International Studies at the University of Bristol. Bridget Anderson is well-known for her defence of No Borders, you can watch her TED talk here, as well as her 2013 book Us and Them? The Dangerous Politics of Immigration Control.