Lingual appliance therapy has moved in and out of public and professional favor. Over the years, the appliance and the techniques have been improved dramatically and, as a result, a reliable system has emerged. It has now undergone many years of clinical experience and has been shown to consistently produce satisfactory results. Esthetic concerns were initially responsible for the development of the appliance system and they continue to remain at the forefront for a significant segment of patients seeking orthodontic treatment. Appearance is undoubtedly the most important motivating factor for adults whether it is termed "facial appearance," "dental appearance," or "straight teeth." Research has shown that physically attractive people achieve higher levels of success in many aspects of life than unattractive people. This book is an attempt to present an overview of lingual orthodontics.