Disorders of the temporomandibular joint (TMJ) sometimes result from minor head trauma. The TMJ has been referred to as the “great impostor” because disorders that affect this area can mimic so many other pain syndromes and pathological processes of the head and neck area (Table 11.1). It is important, therefore, that the clinician learn about the signs and symptoms of TMJ disease so that disorders of this area can be correctly included or excluded in a differential diagnosis when appropriate. The purpose of this chapter is to outline the most current concepts regarding multidisciplinary understanding of TMJ disorders. This will be useful information for the specialist and non-specialist. Diagnosis, therapy, and current suggested research are included.