Over the past decade, the EU and China have expanded their relations beyond a focus on economic and trade issues into the sphere of security. This is particularly evident when security is seen to encompass a variety of policy domains-from traditional, military security to nontraditional human security. However, this development has not followed an even or linear path: The record of EU-China security cooperation has been varied across different policy domains, with distinct temporal trajectories. This article addresses the question of why security cooperation between the two sides has advanced in certain policy domains while having faltered in others. Based on an expert survey of European and Chinese scholars, we explore both interest-driven...