Professor Davies is regarded as a world expert in the management of venous disorder. He is the editor in chief of Phlebology (the only worldwide English language journal dealing with venous disease), past president of the European Venous Forum and the Venous Forum at The Royal Society of Medicine. He is a member of the American Venous Forum, the American College of Phlebology, Vascular Surgical Society of Great Britain and Ireland, and the European Society of Vascular Surgery.