1894
Dr. Harry W. Still (son of A.T. Still, MD, DO founder of osteopathic medicine) was the first DO to establish a permanent practice in Illinois.
1899
The first legislative recognition of Osteopathy in Illinois. DOs were examined by the Medical Board as “Other Practitioners”, could not be called doctors, and had no legal rights to be a physician.
1900
American College of Osteopathic Medicine and Surgery was founded in Chicago.
1902
Chicago School of Osteopathy was founded in Chicago.
1903
The Illinois Osteopathic Association was incorporated in Illinois.
1904
The Chicago School of Osteopathy was absorbed by the American College of Osteopathic Medicine and Surgery.
1913
The American College of Osteopathic Medicine and Surgery changed its name to the Chicago College of Osteopathy.
1913
A.T. Still Research Institute laboratories open in Chicago. Closed in 1918.
1920
First meeting of the American Osteopathic Association (AOA) House of Delegates held in June at the Sherman Hotel in Chicago.
1922
AOA headquarters moved to Chicago.
1923
Illinois law was changed to allow Doctors of Osteopathic Medicine to be examined in—and legally practice—Obstetrics.
1952
The Articles of Incorporation of the Illinois Association of Osteopathic Physicians and Surgeons were filed with the Illinois Secretary of State. The IAOPS would become the Illinois Osteopathic Medical Society (IOMS) in 1999.
1955
The Illinois Supreme Court hands down decision approving the Chicago College of Osteopathy as a school qualified to teach medicine and surgery in all of its branches.
1999
The Illinois Association of Osteopathic Physicians and Surgeons changed its name to the Illinois Osteopathic Medical Society.