The European Union is a leading actor in international development, providing more than half of the world's foreign aid, but also a unique case, combining the characteristics of a bilateral and a multilateral donor. Despite the general acknowledgment that policy coordination substantially improves both the effectiveness of foreign aid and the visibility of the EU in the international arena, Member States have consistently resisted any intrusion into what they consider a key area of their national sovereignty. The increases in volume of aid, the ambitious agenda on aid effectiveness, and...