The three plane of space in which malocclusion exists are Vertical, Transverse and Horizontal. For a complete and proper treatment planning one must consider to correct discrepancies lying in all the three planes. The correction of transverse maxillary deficiency can be an important component of an Orthodontic treatment plan. Control of transverse discrepancies in the correction of dentofacial deformities is extremely important for the ultimate satisfactory achievement of a stable and functional occlusion. Trained Orthodontists can carefully analyze each problem presented, and make decisions on the basis of their scientific and clinical training. Thus,this book is an attempt to create a better understanding of management of transverse dysplasias as an important part of Orthodontic treatment modality which can be a very valid solution to many space problems during treatment.