A Practical Guide to Conquering the World

Thomas Charles Louis Holt (born 13 September 1961) is a British novelist. In addition to fiction published under his own name, he writes fantasy under the pseudonym K. J. Parker.

Holt was born in London, the son of novelist Hazel Holt, and was educated at Westminster School, Wadham College, Oxford, and The College of Law, London. He worked as a solicitor in Somerset for seven years before writing full-time.

His works include mythopoeic novels which parody or take as their theme various aspects of mythology, history, or literature and develop them in new and often humorous ways. He has also written a number of historical novels writing as Thomas Holt. Steve Nallon collaborated with Holt to write I, Margaret, a satirical autobiography of Margaret Thatcher published in 1989.

K. J. Parker is the pseudonym under which Holt has published fantasy fiction. Holt's assumed identity as K. J. Parker was kept secret for 17 years, until April 2015.

While Parker's stories take place in secondary worlds with fictional geographies and world history, some of the typical features of fantasy fiction such as explicit use of magic are not present in his novels. His short stories, on the other hand, frequently deal with magic and the problems it brings for sorcerers. The stories tend to have tragic themes with characters whose actions are unintentionally, ultimately self-destructive. Other major themes in the books are politics, technology (especially disruptive innovation), and either or both of the former as a means to power.