In this Revised Edition of The Secrets Guard Themselves, Bret Gordon expands upon his groundbreaking exploration of Aiki and internal power with new insights, refined explanations, and practical training methods developed through years of continued research and hands-on experience. Drawing from both classical martial traditions and modern scientific understanding, Gordon reveals the principles that underlie the extraordinary abilities demonstrated by the old masters, teaching not only how to cultivate these qualities, but how to apply them effectively in contemporary martial arts. Written for dedicated martial artists, instructors, and serious students, this book provides a comprehensive guide to developing the elusive qualities of internal power that have fascinated practitioners for centuries. Through clear instruction and practical examples, Gordon demonstrates how the principles of Aiki can fundamentally transform movement, structure, balance, and the application of technique, regardless of style or system. More than a collection of theories, The Secrets Guard Themselves presents a complete framework for internal development. By bridging traditional martial wisdom with modern biomechanics, neuroscience, and connective tissue research, Gordon offers a fresh perspective on ancient principles without sacrificing their practical effectiveness. This volume also serves as an official publication for the art of American Yoshinkan Aiki Jujutsu, preserving the principles, training methods, and philosophy of the art for future generations. It stands as both a practical training guide and a permanent record of a living martial tradition. Whether revisiting the original work or discovering these concepts for the first time, readers will gain the tools to deepen their understanding, refine their training, and unlock the skills that have long seemed beyond reach. The secrets have never been hidden. They have always guarded themselves.