Why Institutional Overlap Matters: CSDP in the European Security Architecture

The creation and continued existence of CSDP cannot be understood without reference to the institutional environment within which it is located. To explain its emergence and design, one needs to study the institutional architecture into which this additional institution emerged. Once institutional overlap exists, it becomes a crucial independent variable explaining not only the strategies that member states have at their disposal, but also the development of international institutions occupying the same policy domain as well as the impact on the policy field at large.