Ati Yoga (lit. - shin tu rnal 'byor)-- see also rdzogs pa chen po; and Dzogchen. The third of the Three Inner Tantras. It emphasizes, according to Jamgön Kongtrül the First, the view that liberation is revealed through growing accustomed to insight into the nature of primordial enlightenment, free from accepting and rejecting, hope and fear. The more common word for Ati Yoga nowadays is 'Dzogchen.' The Ati Yoga teachings first appeared in this world to Garab Dorje in the country of Uddiyana to the west of India.
According to The Narration of the Precious Revelation of the Terma Treasures by Longchen Rabjam (p. 87-88), the great master Padmasambhava described the teaching of Ati Yoga in the following way before imparting them to Yeshe Tsogyal: "It is an instruction unlike any I have given in the past, the summit which transcends all of the nine gradual vehicles. By seeing its vital point, mind-made views and meditations are shattered. The paths and levels are perfected with no need for struggle. Disturbing emotions are liberated into their natural state without any need for reform or remedy. This instruction brings realization of a fruition within oneself which is not produced by or from causes. This instantly brings forth spontaneously present realization, liberates the material body of flesh and blood into the luminous sambhogakaya within this very lifetime, and enables you to capture the permanent abode, the precious dharmakaya realm of spontaneous presence, within three years, in the domain of Akanishtha. I possess such an instruction and I shall teach it to you!" See also Great Perfection and Dzogchen.