The Boston Brace System developed in the early 1970's by Dr John Hall and Bill Miller, CPO, is a logical, multidisciplinary approach to the treatment of idiopathic scoliosis. The Brace itself is but one component of the Brace system. The clinical team consists of patient, family, orthopedist, orthotist, physical therapist and nurse. Each team member needs to have a working knowledge of each others discipline, and educate the patient on his/her roll of the treatment plan. If the patient is not educated and understands the process, the logic behind the process and the critical roll they play- then the whole system has been compromised. The Boston Brace itself is one of the most widely studied orthosis used in the conservative management of scoliosis. It has been shown that orthotist training and skill, as well as the ability to assess and modify the fit in 3D have a positive influence on patient outcome. This chapter will discuss the philosophy, biomechanics, design, fit and adjustments necessary for a successful outcome. By following the basic tenants of the system, and maintaining the patient focus, the goal of having a stable spine in adulthood can be obtained. It takes a team effort. This outline will take about how to construct and evaluate the orthosis to maximize fit and function.