This is a widely acclaimed book. In it, we have expounded upon the Sufi spiritual practice in a manner that is both theoretical and original. The book was written after gaining an understanding of Sufism through ten years of living in a Sufi ashram. It also chronicles the lives and teachings of 27 prominent Sufi saints from around the world. A distinctive feature of this work is that it provides, for the first time, a collective account of the Indian masters of the Uwaisiya Sufi lineage. Some of the key saints featured include Khwaja Sahib, Sarmad, Rabia Basri, Nizamuddin Auliya, Amir Khusro, Jogiya Darvesh, Shah Latif, and the Sindhi saint Chainrai Sami.