“The Key to Theosophy” is one of the fundamental works of H. P. Blavatsky (1831-1891), in which the basics of Theosophy are given in an accessible and popular form (answers to questions). The book touches on all the most relevant theosophical discourses: what is the Theosophical Society and who are Theosophists; the goals of the Theosophical Society, forms of its activity, attitude to politics and money; about the moral improvement of man, about God and prayer, about the sevenfold nature of the macro- and microcosm; spirit, soul, mystery of the human “I”; karma and reincarnation; Mahatmas are the teachers of humanity. The book is intended for those who are interested in Theosophy and follow the path of spiritual development.