This book presents a comprehensive, systematic analysis of Russia– Iran relations in the period following the collapse of the Soviet Union in 1991. It discusses the key areas – such as trade, arms sales, nuclear developments, and potential areas of friction in the Caspian Sea – where co-operation is possible; charts different phases of increasing and declining co-operation; and relates these changes to security considerations and domestic factors in both countries. Throughout, the book argues that the potential for co-operation between the two countries is much greater than people realize, and it concludes by assessing how Russia–Iran relations are likely to develop in future.