This document is an introduction to a book about fundamentals of piano practice by Chuan C. Chang. It discusses the author's motivation for writing the book, which was to preserve the teachings of his daughter's piano teacher, Mlle. Yvonne Combe, who was a disciple of Debussy. The book contains two chapters, the first on piano technique and the second on tuning pianos. It provides many examples and exercises to help readers improve their technique. The introduction explains that the material in the first chapter is based on the teaching methods of Mlle. Combe.