This is perhaps the most detailed commentary, most English-expressed translation of the Hatha Yoga Pradipika with profuse illustrations of what happens in the subtle body of a yogi who is proficient in kundalini manipulation for subtle body transformation. Some diagrams show what happens in the subtle body of a yogi who masters this process. The tantric aspects of controlled psyche-arresting sexual intercourse is plainly discusses just as Swatmarama Mahayogin did in the Sanskrit original but with more details in the commentary of exactly how that is done. This is the theory. A reader is responsible for the practice but there is sufficient exposition. Any ascetic can use this information to develop a kundalini yoga practice. The raja yoga integration of remaining introverted while being externally occupied is explained. Kundalini yoga as it is described in the Hatha Yoga Pradipika is a complicated mix of ascetic practices, but if the student learns each of the aspects from a competent teacher, it can be mastered. This book is the syllabus for such education and gives the theoretical platform for this.