This text presents an easy-to-understand guide to the development, design and surgical application of the keystone island flap. Extensive use is made of clinical cases accompanied by intraoperative videos and detailed photography showing the operative sequence and post-operative results (with any complications detailed), in order to maximise the reader’s understanding. Additional information, such as the history, neurovascular anatomy based on dermatomal delineations, the reconstructive alternatives and technical refinements, is presented in boxed sections. The book discusses in detail the design elements including flap physiology upon which the keystone island flap is based. Following a general discussion of the flap and the basis of how it works, including hypothesis (the subject of separate investigation), the authors examine specific defects in various regions of the body and show how keystone island flaps have been used successfully in a wide range of applications. The use of the keystone island flap for specific surgical specialities, including head and neck , melanoma, trauma (including compound fractures of the lower limb) and even irradiated tissue is also addressed. This surgical method can be a valuable supplement to the reconstructive repertoire in the field of reparative surgery.