The first school of osteopathy was founded at Kirksville, Mo., in 1892. A growing number of other colleges in the United States are accredited by the American Osteopathic Association to give the required four-year course of training and to grant the degree of D.O. (Doctor of Osteopathy). These colleges give a complete course of instruction in conventional medicine as well as in osteopathic theory and practice. Osteopaths are licensed to practice medicine, including surgery and the prescription of drugs, throughout the United States. Many specialize in treating bone and muscle conditions, but about half are primary-care physicians in general medical practice.