Russian resurgence in the international arena has been one of the most controversial topics in European security in recent months. What drives Russian foreign policy at the end of the Putin era? Does it reflect the intensifying domestic struggle between factions and interest groups manoeuvring for dominance of the Kremlin? Is Russian international behaviour a product of the commercial pursuits of Russian energy exporters? Is it a policy fuelled by neoimperial ambition and desire to bring back under Moscow's control lands conquered by a succession of Russian emperors over more than two centuries? Or are we witnessing Moscow's painful adaptation to its new, diminished circumstances, and its attempts to develop a new international posture in relation to militarily vastly superior neighbours in Europe and Asia? And, last but not least, how should Europe and the United States respond to the new Russian foreign policy? These are the questions that will be addressed in this Adelphi Paper.This paper will examine the key drivers of Russian foreign policy - domestic politics and economic, military and security considerations - and conclude with recommendations for Western policymakers on how to deal with Russia's return to the international arena as an assertive actor after its long period of introspection and preoccupation with domestic troubles. This paper should be of interest to scholars, policymakers and non-specialists interested in Russia and international relations.