This book is a lengthy treatise on Magick, Aleister Crowley's system of Western occult practice, synthesised from many sources, including Eastern Yoga, Hermeticism, medieval grimoires, contemporary magical theories from writers like Eliphas Levi and Helena Blavatsky, and his own original contributions. The first part of the book, "Mysticism" is essentially Crowley's system of yoga, which is designed to still the mind and enable single-pointed concentration. The second part, "Magick", deals with the accessories of ceremonial magick in detail. Subjects include: the temple, the magick circle, the altar, the scourge, dagger, and chain, the holy oil, the wand, cup, sword, pentacle, lamp, crown, robe, book, bell, lamen, and the Magick Fire.

Aleister Crowley (1875 – 1947) was an English occultist, ceremonial magician, poet, painter, novelist, and mountaineer. He founded the religion of Thelema, identifying himself as the prophet entrusted with guiding humanity into the Æon of Horus in the early 20th century.