The field of Physical Medicine and Rehabilitation began in the 1930s to address musculoskeletal and neurological problems. It broadened its scope considerably after World War II. As thousands of veterans came back to the United States with serious disabilities, the task of helping to restore them to productive lives became a new direction for the field. The Advisory Board of Medical Specialties granted PMR its approval as a specialty of medicine in 1947. The specialty experienced an evolution in the 1990s to provide state of the art sub-specialty training in many fields including musculoskeletal and procedural pain management.