The significance of the Baltic Sea Region to European security has increased. The military-strategic situation in the region has deteriorated and the region has become less secure. The complexity and scale of the challenges at hand means that no European state can face them alone. The need for cooperation is greater than ever. Several actors have a significant role in contributing to the security in Northern Europe, and bilateral and multilateral cooperation are corner stones in building security together. As part of this the Nordic-Baltic cooperation keeps developing. What has been done so far and what are the next steps?