States with the ability to use a combination of sensors and long-range missiles to prevent adversaries from operating in an exclusion zone, or "bubble", adjacent to their territory are said to possess anti-access/area denial (A2/AD) capabilities. This study examines Russia's A2/AD systems and their implications for the Baltic Sea region. Much has in recent years been made of Russia's new capabilities and the impact they might have on the ability of NATO member states to reinforce or defend the vulnerable Baltic states in case of crisis or war. On closer inspection, however, Russia's capabilities are not quite as daunting, especially if potential countermeasures are factored in. In particular, surface-to-air missile systems currently create much smaller A2/AD bubbles than is often assumed and a number of countermeasures are possible. Experiences from Syria also raise questions about the actual capabilities of such systems in combat, relative to their nominal capabilities. Anti-ship and anti-land systems pose a greater threat but, here too, countermeasures are available. The dynamics of this strategic vortex affect Sweden directly and indirectly. This is one of the reasons why Sweden's security is increasingly interlocked with that of its neighbours and of the transatlantic alliance.