The Great Reformer is the English translation of Mujaddid-e-Azam, a comprehensive biography of the Mujjadid (Reformer in Islam) and Founder of the Ahmadiyya Movement Hazrat Mirza Ghulam Ahmad by a close associate and compatriot, Dr. Basharat Ahmad.

This monumental research work published in Urdu in three volumes was translated into English in 2008 by Hamid Rahman, PhD. It is widely considered to be the most authentic and complete portrayal of the great and tireless service rendered to Islam by the Founder of the Ahmadiyya Movement. The first two volumes, published in 1939 and 1940 respectively, consist of the Founder's life history, and also contain synopsis of each of his major Urdu, Arabic and Persian works. The third volume deals with his Islamic philosophy, thoughts, exposition of Islamic concepts, defense of Islam in reply to non-Muslim critics, and his mission of carrying the message of Islam to the West.