Srimad-Bhagavatam, 18 Volumes, Cantos 1-12

The Bhagavatam's eighteen thousand verses consist of hundreds of conversations—spoken between yogis, sages, and self-realized kings of the ancient world—on how to achieve life's ultimate perfection. Their discussions frequently center on various incarnations of Krishna—the Supreme Person—and descriptions of His pastimes with His devotees. The entire work was compiled by Vyasadeva—editor of the Vedas—as his own commentary on Vedanta-sutra, the essence of all theistic knowledge.
The Bhagavatam is also known as the Bhagavat Purana, one of the eighteen Puranas (supplemental works) in the Vedic tradition. It is presented in twelve cantos—volumes—each of which deals with a specific aspect of the Absolute Truth, the original and supreme cause of all causes. The main theme running throughout the Bhagavatam is the science and practice of bhakti-yoga, devotional service to the Supreme Person.