[citation needed] Stewart began working at St Thomas' Hospital in London, England at the age of 23, as a special probationer in the Nightingale Training School for Nurses.

[citation needed] Stewart left St Thomas' in 1885 when she was chosen to become matron at a smallpox hospital in Darenth, near Kent, England.

Stewart died on March 6, 1910, in Chilworth, Surrey in the presence of her dear friend, who was once matron of St Bartholomew's, Ethel Gordon Fenwick.

[citation needed] Stewart introduced a more efficient and orderly nursing program, based upon a solid education.

Effectively combining education and professional organization brought Stewart and her ideals respected around the world.

Stewart illustrated that her intellect and diligence was equal to those of her superiors through her continuing reputation within the medical community.