Vedanta philosophy acknowledges the Prasthana Trayi as its three authoritative primary sources. The texts comprising the Prasthana Trayi are the Upanishads, the Bhagavadgita and the Brahma Sutra. The Upanishads are the sruti prasthana, the revealed texts (sruti - that which is heard); the Bhagavadgita is the smriti prasthana, composed by sages based on their understanding of the Vedas (smriti - that which is remembered); the Brahma Sutra is the nyaya prasthana, the logical text that sets forth the philosophy systematically (nyaya - logic/order). No study of Vedanta is considered complete without a close examination of the Prasthana Trayi.

While the Upanishads and the Bhagavadgita are authoritative Vedanta texts, it is in the Brahma Sutra that the teachings of Vedanta are set forth in a systematic and logical order. The Brahma Sutra is known by many names: it is also called the Vedanta Sutra, Uttara-mimamsa Sutra, Shariraka Sutra and the Bhikshu Sutra.

The Brahma Sutra consists of 555 aphorisms or sutras, in 4 chapters, each chapter being divided into 4 sections each. The first chapter (Samanvaya: harmony) explains that all the Vedantic texts talk of Brahman, the ultimate reality, which is the goal of life. The second chapter (Avirodha: non-conflict) discusses and refutes the possible objections against Vedanta philosophy. The third chapter (Sadhana: the means) describes the process by which ultimate emancipation can be achieved. The fourth chapter (Phala: the fruit) talks of the state that is achieved in final emancipation.

Indian tradition identifies Badrayana, the author of the Brahma Sutra, with Vyasa, the compiler of the Vedas. Many commentaries have been written on this text, the earliest extant one being the one by Adi Sankara. Later commentators include Bhaskara, Yadavaprakasha, Ramanuja, Keshava, Neelakantha, Madhva, Baladeva, Vallabha, Vijnana Bhikshu, Vacaspati and Padmapada. Among all these, and other commentaries, Sankara's commentary is considered as an exemplary model of how a commentary should be written, and most commentators are influenced by it, even when they disagree with Sankara's interpretations.