Learning to deploy civilian capabilities: How the United Nations, Organization for Security and Co-operation in Europe and European Union have changed their crisis management institutions

International organizations continuously deploy civilian capabilities as part of their peacekeeping and crisis management operations. This presents them with significant challenges. Not only are civilian deployments rapidly increasing in quantity, but civilian missions are also very diverse in nature. This article analyses how international organizations have learned to deploy their civilian capabilities to deal with a growing number and fast evolving types of operations. Whereas the previous literature has addressed this question for individual international organizations, this article uniquely compares developments in the United Nations (UN), European Union (EU) and Organization for Security and Co-operation in Europe (OSCE), three of the largest civilian actors. Drawing on the concept of organizational learning, it shows that all three organizations have made significant changes over the last decade in their civilian capabilities. The extent of these changes, however, varies across these organizations. The article highlights that the EU, despite its more homogeneous and wealthier membership, has not been able to better learn to deploy its civilian capabilities than the UN or OSCE. We show that the ability of these organizations to learn is, instead, highly dependent on institutional factors.