This is an absolutely indispensable book for every practitioner of Tibetan Buddhism. If you've received the Vajrakilaya empowerment, this guide contains everything you need to know about the sadhana and how to prepare and accomplish a retreat along with it. Garchen Rinpoche is a great bodhisattva of our time--He regularly displays miracles to his followers, and has devoted his life to practicing the dharma after spending 20 years in a Chinese prison/labor camp. This book will certainly be of benefit to you even if you're only casually interested. Om ah hung