The purpose of this project was to expand the literature on cranio-somatic relationships by identifying previously undocumented functional interactions between specific areas of superficial cranial tissue and specific distal somatic elements. The specific questions for this project focused on functional neuromusculoskeletal interactions observed between somatic tissues and cranial tissues. These interactions were documented in Facilitated Pathways Intervention (FPI), a manual therapy guide. The information in this guide is based on clinical observations of 214 individuals (aged 2 to 77 years) clinically treated by the author over a period of six years. The therapeutic intervention primarily treated musculoskeletal pain and dysfunction utilizing FPI techniques that were augmented by subsequent documentation of observed cranio-somatic relationships. The clinical observations are documented in the FPI manual and show an extensive system of functional cranio-somatic relationships. A graphic, Homunculus of the External Cranium (HEC) evolved in the development of the FPI guide and is presented in six illustrations. The graphic is accompanied by a table of 101 muscles and joints detailing the cranio-somatic relationships. Another table presents the somatotopic framework of the identified relationships. The FPI manual details the myofascial procedures, methods, and therapeutic applications. Theoretical and practical implications and recommendations regarding the treatment of neuromuscular dysfunctions are discussed.