This document discusses the history and development of bonding in orthodontics. It describes the evolution from early chemical cure and light cure bonding agents to today's dual cure and self-etch primers. The mechanisms of bonding and various bonding agent types are explained. The document reviews the bonding procedure and limitations. It also examines bonding to different surfaces like enamel, gold, composite and porcelain. Advances in moisture resistant and moisture tolerant adhesives are highlighted.