Over the course of the last millennium in Tibet, some tantric yogins have taken on norm-overturning modes of behavior, including provoking others to violence, publicly consuming filth, having sex, and dressing in human remains. While these individuals were called 'mad,' their apparent mental unwellness was not seen as resulting from any unfortunate circumstance, but symptomatic of having achieved a higher state of existence through religious practice. This book is the first comprehensive study of these 'holy madmen,' who have captured the imaginations of Tibetans and Westerners alike. Focusing on the lives and works of three 'holy madmen' from the fifteenth century - the Madman of Tsang (Tsangnyon Heruka, or Sangye Gyeltsen, 1452-1507, and author of The Life of Milarepa), the Madman of U (Unyon Kungpa Sangpo, 1458-1532), and the Madman of the Drukpa Kagyu (Drukpa Kunle, 1455-1529). DiValerio shows how literary representations of these madmen came to play a role in the formation of sectarian identities and the historical mythologies of various sects. DiValerio also conveys a well-rounded understanding of the human beings behind these colorful personas by looking at the trajectories of their lives, their religious practices and their literary works, all in their due historical context. In the process he ranges from lesser-known tantric practices to central Tibetan politics to the nature of sainthood, and the 'holy madmen' emerge as self-aware and purposeful individuals who were anything but crazy.