The key to successful orthodontic treatment depends not only on manual skills and knowledge of treatment steps but also on knowledge and choice of materials being used. Today more than hundred years have passed since Dr. Edward Angle placed his first archwire into patient's mouth and orthodontics began. It was during that period many innovations did occur that have been explained in terms of art. As time passed scientifically based orthodontics evolved and we see from that time much innovation in material science have supped up with new treatment approach and modalities. Wires being one of the major component of orthodontic appliances are discussed in this book in terms of composition, properties, uses and rationale for there selection in various clinical situations.