The author, Shizuka Ishido, is a master of Iaido (Hanshi 8th Dan), Jodo (Kyoshi 8th Dan), and Kendo (Kyoshi 7th Dan). With extensive experience traveling abroad, he possesses a wealth of knowledge and is renowned for his teaching methods that are easy for a wide audience to understand. His famous book, "Iaido Lecture: Enjoying the Principles - All Japan Kendo Federation Iaido Edition," provides clear explanations of the often-difficult principles of the "techniques" (waza), offering insights to those practicing Iaido. "Iaido Lecture: Enjoying the Principles" is an explanation of the All Japan Kendo Federation's Iaido curriculum. This book, "Iaido Lecture: Enjoying the Principles - Koryu Edition," explores the various techniques of the old-style swordsmanship (koryu kenjutsu), examining the assumptions behind each technique and the underlying principles that govern their movements. Master Ishido, who has sought the true meaning and essence of Iaido, generously shares the techniques (waza) and principles (riai) he has cultivated. I purchased this book for reference and have only opened it a few times. This book is out of print, and it will undoubtedly become increasingly difficult to obtain in the future.