Bonding to enamel has over 50 years of history. Efforts have been made to develop or introduce a simplified alternative, but enamel acid etching remains the most effective procedure for stable enamel bonding. Although acid etching is considered the most popular procedure in dentistry, there are characteristics that deserve special attention because of how crucial they can be in many clinical situations. This article reviews some of these aspects of enamel bonding using the acid-etching technique.