The mysteries of Tantra have engrossed countless meditators for centuries. Since the time of Buddha, these secrets have been passed down from accomplished master to disciple largely by word of mouth. Now drawing from his own experience and the works of Je Tsongkhapa and other great Tibetan Yogis, Geshe Kelsang clearly sets out all the stages of the four classes of Tantra, giving a full explanation of generation and completion stages. Tantra is revealed as the gateway to a blissful new world. The book represents a significant milestone in revealing these profound mysteries to the contemporary world.