The book gives all the relevant information about the A.'.A.'., Mystical & Magical system of spiritual attainment, created by A.Crowley and C.S.Jones in 20th Century. It covers the historical facts in detail, elaborates on essential ideas behind the System, and then goes on with presenting - in a systematic and clear manner - each one of the Steps along the Path from the Student phase up to Adeptus Exemptus grade. Appendices at the end of the book include all the basic reading material for anyone interested in exploring the A.'.A.'. System through personal experience.