The Key to Theosophy (1889) by Helena Petrovna Blavatsky is a structured, question-and-answer guide designed to introduce the foundational ethics, science, and philosophy of the Theosophical Society. It serves as an accessible "key" to the deeper, esoteric studies found in her more complex works, such as The Secret Doctrine. The book also distinguishes modern Theosophy from Buddhism, clarifying that while they share similar ethics, Theosophy is broader and focuses on the "Wisdomism" (Budhism) rather than just the religion of Gautama Buddha. It concludes by discussing the future of the Society and the role of the "Masters" or Mahatmas in preserving this ancient knowledge.