The author begins with the outward aspects of the teaching most likely to puzzle the student coming fresh to the subject. He considers various attitudes to Sufi ideas, and evidence of their absorption into medieval Christianity, Hinduism, Jewish mysticism and modern philosophical teachings.

Shah gives potted biographies of some of the best-known Sufis of the ages, adding descriptions of four of the major Sufi orders: the Chisti, Qadiri, Suhrawardi and Naqshbandi. In addition there are a number of Sufi teaching stories as well as question-and-answer sessions with Sufi teachers.

The greater part of the book illuminates aspects of Sufi activity and practice relevant to the contemporary world.

The New York Times also applauded the book, saying it was ‘like a door opening where one least expects it’.