The term Physicians in the U.S. is given to qualified, licensed practioners of medicine. Physicians should hold either Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO) degree. Many other countries have a broader interpretation of the word. As the field of medicine becomes more and more specialzied, so does the specialty of the physicians. This requires further training in that specialzed field. Besides specializing in particular body systems (vascular) or pariculare organs (eyes); today there are physicians who limit their practice to seniors and their health concers. Likewise there are physicians who care specially for the needs of womens'conerns, or men's health issues, or infants or children.