Partner, Aston and Stone, Architects, San Francisco, CA, c. 1890; Partner, Stone and Munson, Architects, San Francisco, CA, c. 1890-1894; Principal, Louis S. Stone, Architect, Stockton, CA; Principal, Louis S. Stone, Architect, Oakland, CA, c. 1909; in 1909, Stone maintained an office in Room 268 of the Bacon Building, Oakland, CA;

In 1908, Stone was listed as an Architectural Editor of the Architect and Engineer of California. (See Architect and Engineer of California, 13:2, 06/1908, p. 78.) In October 1918, it was reported in the Western Architect that Louis S. Stone was working with the Young Men's Christian Association to help rebuild France.

Louis S. Stone married Emma Mills (b. California, 10/07/1862-d. Alameda County, CA, 10/16/1952) of Santa Rosa, CA, 12/15/1889 near Santa Rosa.

In 1909, Stone had plans for school buildings accepted by the Boards of Education in Coalinga, CA, and Fresno, CA. The Coalinga grammar school had a budget of $40,000; the Fresno school would cost approximately $60,000.