The current book discusses a new and old topic at the same time. Shia Islam, as a doctrine and community, has emerged as a major problematic issue since the early days of Islam and continues to be so until now, as it is considered the largest minority among Muslims in the Middle East.The book provides a general explanation of the Hawza of Najaf, as the most important and oldest Hawza in the Shia world, and the study atmosphere within it. It also explores the most significant aspects of the theory of the highest Shia authority, Ali al-Sistani, in nation-building in Iraq after 2003. Examining the political theory of al-Sistani involves its own complexities within the Iraqi context, as well as the challenges faced by his authority in light of diverse visions within the Hawzas of Qom and Najaf.