Horace Everett Hooper (December 8, 1859 – June 13, 1922) was the publisher of Encyclopædia Britannica from 1897 until his death.

He relocated to Chicago, Illinois in 1893 to join the company of James Clark, publishers of cheap editions.

He marketed their reprint of the Century Dictionary using mail order and credit by installment terms, to great success.

He also noted that The Times suffered decreasing sales, and had on the idea of using the latter to market the former — to their mutual benefit.

Hooper bought the copyright, and began the production of eleven additional volumes to make the 10th edition, which was published by The Times in 1902–3.