For thousands of years, people on a spiritual quest have consulted the mystical, intensely philosophical Upanishads. As the name implies (upa-near; ni-down; shad-to sit), one is advised to sit near a spiritual teacher to learn. To learn what? This Upanishad's name gives the clue: Isha means "the supreme controller." Let us sit near the spiritual guide to learn about the supreme controller: God. The process is simple, provided one learns from an authentic guide. The translation and commentary of A. C. Bhaktivedanta Swami Prabhupada strictly adheres to the book's intention, assuring you of a legitimate understanding of the depths of Upanishadic knowledge.