‘Lewis’ is an original book that pushes theoretical boundaries and investigates why states cooperate. It comes up with a, perhaps, counterintuitive answer: because state actors do not want to integrate. Cooperation is, hence, their (next best) alternative. Looking at Luxemburg, France and the US – and a multitude of actors within these states – Lewis draws on a wealth of information, and provides a thought-provoking argument; as well as an interesting read.’-Bernhard Blumenau, The University of St Andrews, UK