Thoracic Outlet Syndrome (TOS) is a fairly common diagnosis, affecting approximately 8% of the population. Pain with TOS often presents anywhere between the neck, face, occipital region or into the chest, shoulder, with paresthesia into the upper extremity based on where the symptoms are originating from. Similar to other conditions, this diagnosis encompasses a host of signs and symptoms, yet does not always tell us the specific pain generator. TOS can be broken down into neurogenic TOS (95-98% of cases according to Davidovic et al. 2003) vs. vascular TOS (1). Furthermore, vascular TOS can further be subdivided into either Arterial TOS or Venous TOS. In this article, we will help you understand what thoracic outlet syndrome is, the causes behind it, and excellent exercises for thoracic outlet syndrome!