Regional security in Europe is decided as much at its edges as in its capitals. From the Baltic Sea to the Black Sea, the Western Balkans to the High North, regional flashpoints shape the wider contest between democratic states and authoritarian challengers. This hub follows the security dynamics of Europe’s most exposed regions: deterrence on NATO’s eastern flank, Ukraine security and the defense of its neighbors, frozen and active conflicts in the Western Balkans and the Caucasus, and Black Sea security in a contested maritime domain. Ukraine security now anchors the wider debate over regional security, pressure on NATO’s eastern flank keeps allied deterrence in focus, and Black Sea security has become a test of Western resolve. Fellows and analysts assess force posture, alliance politics, and the local drivers of instability that outside powers seek to exploit. Explore expert analysis and commentary on the regional security challenges facing the Euro-Atlantic community.