This book offers a comprehensive survey of the formative period of Sufism - the main mystical tradition in Islam - from the ninth to the eleventh century. Both the literature in the area and issues and questions that await further study are explored within an interpretive framework. The major themes of the book include the following: growing out of traditionalist approaches to Islam during the ninth century, Sufism originally took shape in Iraq, especially Baghdad, and rapidly spread to other regions of the Islamic world. There were mystical trends outside Iraq, but they gradually blended into Sufism; early Sufis attempted to turn away from everything 'other-than-God' and orient themselves solely towards the Divine, but this attempt took multiple forms.