In the absence of any other physical treatment, Postural Reconstruction (PR) as a physical therapy approach for the pain and dysfunction attributed to ankylosing spondylitis (AS) was followed by the elimination of the need for pain medication and the restoration of full function for a 28-year old female. Patients with AS suffer pain and stiffness causing often severe functional losses. The management of patients with this disease is largely by medication (analgesics, NSAIDs and corticosteroids), physical therapy, and sometimes radical surgery in severely advanced stages of the disease. This report presents a case study of a patient diagnosed with AS, who was deteriorating over a period of four years while following this conventional approach. The patient showed remarkable improvement in less than one year using the neuromuscular technique of Postural Reconstruction (PR) developed by Françoise Mézières. The field of PR associates pain and dysfunction with muscular imbalance. The existence and significance of this imbalance is determined by trained observation of the patient’s morphology/alignment, and treatment seeks to restore alignment and improve imbalance.