Jamgön Kongtrül Lodrö Thayé (1813-1899), the profoundly learned and realized master who compiled what are known as the Five Great Treasures, wrote the outstanding commentary to The Mahayana Uttaratantra Shastra translated here. Called The Unassailable Lion's Roar, it presents Maitreya's text as a background for the Mahamudra teachings in a way that is especially clear and easy to understand.

Khenpo Tsultrim Gyamtso Rinpoche provided the annotations and the explanations on which the present translation is based. A renowned scholar and highly accomplished yogi, he is a living example of the ongoing tradition of oral transmission.