Maxillary constriction, the most common orthodontic problem are frequently accompanied with significant malocclusion, periodontal damage, functional shift, mandibular asymmetry and narrowing of nasal cavity. This book compiles different management protocols for transverse maxillary deficiency patients in all age groups. More interestingly,an up-to- date summary of the available research in mini implant assisted rapid palatal expansion based on current evidence are represented.