A Series of Lessons in Raja Yoga presents the discipline of mind as a practical path to self-mastery, translating yogic psychology into graduated exercises in concentration, breath awareness, will, perception, and spiritual realization. Written in the lucid, didactic manner characteristic of early twentieth-century metaphysical manuals, it bridges Victorian self-culture, Theosophical currents, and popular Western interest in Indian philosophy, offering not philological scholarship but an influential synthesis of Raja Yoga for modern seekers. William Walker Atkinson, an American lawyer, businessman, and prolific New Thought writer, was deeply engaged with questions of mental power, suggestion, personal magnetism, and spiritual development. Publishing under his own name and several pseudonyms, he helped shape a transatlantic culture of practical occultism. His interest in the trained mind and latent human faculties naturally led him to reinterpret yogic teachings for readers seeking disciplined inner transformation. This volume is recommended for readers interested in the genealogy of modern yoga, New Thought, and Western esotericism, as well as for those drawn to disciplined introspection. Approached critically, it illuminates how yoga was adapted for Western audiences while still offering earnest, methodical reflections on attention, character, and the inward life.