Agha Khan was a Muslim leader who served as the 49th and current Imam of Nizari Ismailism, a denomination of Ismailism within Shia Islam. He succeeded his grandfather, Sir Sultan Muhammad Shah Aga Khan III, as the leader of the Ismaili community in 1957. Agha Khan is also the founder and chairman of the Aga Khan Development Network, an international development organization that works to improve living conditions and opportunities for people in some of the poorest parts of the world.