As a professor of Indo-Tibetan studies, and chair of the religion department at Columbia University, Robert Thurman has had a great career devoted to the task of making the Buddhist teaching and scriptures, particularly those of the Tibetan people, intelligible to students and interested laypersons.
'Tibetan Buddhism increasingly rivals Zen in its popularity as a path of Buddhist wisdom and practice.'
Thurman has written and translated many texts in this area, particularly the well-received 'Tibetan Book of the Dead.' In this book, 'The Essential Tibetan Buddhism,' Thurman does a thorough job at laying out in concise and accessible terms the history and development of Tibetan Buddhism, as well as an explication and explanation of the core beliefs and practices.
Dedicated to the Dali Lama (who I have had the honour to be near during his regular trips to Bloomington, my current home -- his brother has been on faculty at Indiana University), this book shows how Tibetan Buddhism grew out of a sense of having been personally touched by Buddhas dwelling among them. Indeed, Tibetans often take for granted the idea of a constant presence of Buddhas among them. While many varieties of Buddhism allow for the theoretical attainment of the absolute freedom required to be a Buddha, Tibetan Buddhism is rare in accepting that there are many Buddhas currently at hand.
Tibetan Buddhism also preserved the Indian Tantric traditions, as a means for the attainment of complete Buddha-hood. Indeed, some of these Tantras contradict the cosmologies which speculate that there is a cycle of Buddhas, and that another Buddha is not due for thousands of years.
'Thus at least one of the levels (the highest, most would say) of the Tibetan sense of history sees the planet as progressing positively toward a time of unprecedented fulfillment. Tibetan Buddhist society therefore is perhaps unique among Buddhist societies in that the people live within a consciously articulated myth of historical progress, carrying within itself a fascinating complexity.'
Tibetan Buddhism is far from nihilistic, as indeed most Buddhism is not nihilistic. One discovers a unity of awareness and of all creation, something at the heart of many of the great religions of the world, if not so specifically laid out as a premise or as a possible attainment. The Buddha obtains total consciousness, a kind of universal omniscience; this is not to say a Buddha is God or becomes God (in fact, the Buddha will eschew God-like powers and domination over other creatures).
Grant the vision of direct enlightenment,
Whose nature is universal voidness!
The disciple should press her palms together,
Praise the Mentor, and then entreat him:
'Great teacher, grant me the vision
Of direct enlightenment,
Free from evolution and birth,
Beyond the three luminaries...
Complete with original translations of source texts, commentaries, essays of context and interpretation, and a good source of religious studies (history, philosophy, theology, etc.), this is an excellent introduction to the contemplation, study or even practice of Tibetan Buddhism.