This document provides an introduction to the "Sing Like A Professional" guidebook for singing. It discusses how the human voice is a product of coordinated muscles and techniques can only improve this coordination. It emphasizes discovering a technique to perfect the coordinative process through muscles involved in phonation. The guidebook will show a logical path for vocal skill development, focusing on registration theory and the reflexive nature of the vocal response. It presents the voice as a respiratory organ that can be adapted into a sound-producing instrument through muscular contractions of the vocal cords and pharyngeal tract positioning for resonance. The book is suitable for both beginners and experienced singers looking to improve their performance skills.