The author, Shizuru Ishido, is a master instructor with experience as a Hanshi (highest rank) 8th dan in Iaido, Kyoshi 8th dan in Jojutsu, and Kyoshi 7th dan in Kendo. He has traveled extensively overseas and possesses a wealth of experience and insight, earning him a reputation for providing instruction that is easily understood by a wide audience. His renowned work, "Iaido Lecture: Enjoying the Principles - All Japan Kendo Federation Iaido Edition," provides clear explanations of the often-difficult principles behind the techniques, offering valuable insights to those studying Iaido. "Iaido Lecture: Enjoying the Principles" focuses on the All Japan Kendo Federation's Iaido curriculum. This book, "Iaido Lecture: Enjoying the Principles - Koryu Edition," explores the various techniques of classical swordsmanship, examining the scenarios they were designed for and the underlying principles that govern their movements. Ishido, a Hanshi who has dedicated himself to understanding 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, so it will undoubtedly become increasingly difficult to obtain in the future.