This CSIS report examines the evolution of European military capabilities over the next decade. It asks two main questions. What military capabilities might European allies and partners of the United States possess by 2030? And what types of military missions will these states be able (and unable) to effectively perform by 2030? First, European militaries—including the largest and most capable European NATO members—will continue to struggle to conduct several types of missions without significant U.S. assistance. Second, European militaries will face significant challenges in the Indo-Pacific. Third, Europe's major powers will likely have the capability to conduct most types of missions at the lower end of the conflict continuum without significant U.S. military aid. To sustain progress and overcome remaining challenges, NATO will have to revise its burden-sharing metrics, modernize defense planning and procurement practices, and address lagging political will.