Understanding the foreign policy agenda and behavior of the Islamic Republic of Iran is a critical challenge for the world. But where do the principal Iranian regime actors come from in terms of political background, experiences and interests? Which types of ambitions or policy conflicts have dominated and shaped foreign policy debates since 1979? This book explains the internal policy process in Tehran by following two regime personalities, Ali Khamenei, the Supreme Leader, and Akbar Hashemi Rafsanjani, who before his death in January 2017 held some of the most powerful political positions in Iran. No two men have been more influential in dictating the regime's decision-making processes since 1979. Yet little is known about how their competing worldviews and interests, their key moments of dispute - both personal or policy-based - or their personal ambitions have informed the trajectory of Iranian politics. The book analyzes Khamenei and Rafsanjani's own words and writings - and accounts of them given by others - to reveal how the domestic policy contest has shaped Tehran's actions on the regional and international stage. Comprising primary and secondary Iranian sources - including untapped memoirs, newspaper reports, and Iranian electronic media and personal interviews - the book highlights the principal rivalries over the lifespan of the Islamic Republic and offers new insights into the present and future of Iranian foreign policy.