Abstract
The European Union (EU) has fortified its external borders using a number of measures including the creation of new institutions and networks such as FRONTEX and EUROSUR. In non-EU countries such as Turkey, border security is being reorganized with EU support and cooperation. By combining the literature on EU actorness and neo-functionalism, I provide a theoretical toolkit to critically unpack these new developments through conceptualizing multiple dimensions of what I call functional actorness. The contribution analyzes how the functional transformation of EU and Turkish border security has produced a number of side effects which are critically appraised.