Russia's contribution to the development of Iran's nuclear program goes back to the 90s, making Moscow a significant diplomatic actor in the complex issue related to Tehran's alleged underground nuclear agenda. Hence, the choice to write this book stems from the need to explore thoroughly the determinants of Moscow's foreign policy on Iran, with a specific focus on the major domestic actors involved in shaping Moscow's behavior. Kremlin's policies are examined in terms of the overlapping agendas of various domestic lobbies and institutions, and in view of their temporal evolution. The research should be especially useful to those interested in Moscow's foreign policy decision- making and in contemporary Russian history. Focusing on the period from Gorbachev's secretaryship to the end of Putin's presidency, the book completes the study, mainly focused on Medvedev's mandate, carried out in Moscow's Iran Policy and the Nuclear Question: Linking Domestic Decision-Making and Russian-U.S. Relations (2010), by the same author.