The Shī‘a Imami Ismā‘īlī Tariqah also referred to as the Ismā‘īlī or Nizārī (Arabic: النزاريون‎ an-Nizāriyyūn), is a path (tariqah) of Shī‘a Islām, emphasizing social justice, pluralism, and human reason within the framework of the mystical tradition of Islam. The Nizari are the second largest branch of Shia Islam and form the majority of the Ismā‘īlī (Arabic: اسماعیلیه‎). There are an estimated 15 million Nizari Ismā‘īlīs residing in more than 25 countries and territories.

Nizari teachings affirm the Islamic tenet that "there is no god but the One God, and Muhammad is the prophet of God". Like all Shī‘a, Nizaris believe Muhammad's relative Ali was selected by divine decree to succeed the Prophet as Imam or spiritual leader of the Muslim community. This institution of the Imamate continues in an unbroken hereditary chain through Ali and Fatimah, Muhammad's daughter, to the present day, under the aegis of His Highness Prince Shah Karim al-Husayni, the Aga Khan IV, the 49th Nizari Imam.

Human society is believed to be in a state of continuous flux, the role of the Imam is to find permanent solutions to issues, and challenges raised by increasingly rapid changes in the world; to care for the spiritual and material well being of their followers as well as humanity at large, and to safeguard the rights of the individual to spiritual, social, and scientific enquiry.