Many adults who need orthodontic treatment will not accept conventional labial appliances; for them invisible lingual appliances are the only alternative. However, after a hasty introduction which placed many untested appliances on the market, lingual treatment lost its initial attraction and many orthodontists are still skeptical of the concept. Fortunately, new bonding techniques and simplified treatment mechanics have greatly improved the performance of lingual appliances. This report describes the lingual appliance and effective techniques for bonding and rebonding. Appropriate arch wire and patient selection is discussed, as are diagnosis and treatment planning. Four detailed case reports are included which illustrate successful treatment using lingual appliances