nto the English language for the very first time the great physician and meditation adept Yuthok Yonten Gonpo's teachings on Ati Yoga. Ati Yoga (Tib: Dzogchen), literally meaning the 'utmost yoga, ' is the pinnacle of Buddhist Vajrayana practice. It is the most simple, direct, and profound path to reveal the primordial wisdom which is one's basic nature. In his remarkably clear and accessible commentary which seamlessly weaves in verses from Yuthok's own root text and quotations from Tibet's great masters of meditation, Dr Nida Chenagtsang skillfully points us to the sky-like nature of our own mind which is clear, vast, and unobstructed by the clouds of afflictive emotions. Much more than a theoretical exposition, Volume One of Mirror of Light contains precise instruction on Ati Yoga's preliminary practices and trekchod ('cutting through hardness') -- ancient proven techniques that reveal the present fresh awareness that is free from all confusion and beyond the 'hardness' of dualistic thinking.