The temporomandibular joint (TMJ) is the most unique and complex joint in the body. The anatomy of the TMJ varies among mammals depending upon masticatory requirements. Masticatory system function demands that the mandible be capable not only of opening and closing but also of forward, backward, and lateral movements and combinations thereof. In humans, the TMJ is described as a ginglymoarthrodial type of diarthrotic joint. This means that it is not only capable of rotation (movement around a single axis) but also translation (movement around more than one axis at a time). This chapter will provide a review of the growth and development of structures of the masticatory system with special emphasis upon the osseous components.