Richard A. N. Bonnycastle
|Born||September 26, 1934
Winnipeg, Manitoba, Canada
|Education||University of Manitoba|
|Occupation||Publisher, Investor, Conservationist, Racehorse owner/breeder|
|Board member of||Harlequin Enterprises, Torstar Corporation, Cavendish Investing Ltd., Jockey Club of Canada|
|Parent(s)||Richard H. G. Bonnycastle &
Mary Frances Margaret Northwood
|Relatives||Sisters: Honor, Judith Augusta|
Richard Arthur Northwood Bonnycastle (born September 26, 1934 in Winnipeg, Manitoba) is a Canadian businessman who is the former owner and publisher of Harlequin Enterprises and an owner of Thoroughbred racehorses. He is part of the Bonnycastle family founded in Canada by British military officer, Sir Richard Henry Bonnycastle.
Dick Bonnycastle graduated from the University of Manitoba in 1956 and eventually joined Harlequin Enterprises, a romance novel publishing business founded in 1949 by his father, Richard H. G. Bonnycastle. On the death of his father in 1968, Dick Bonnycastle assumed management of Harlequin and would serve as its chairman until 1981. Within a few years of taking over from his father, he moved the company's operations to Toronto, Ontario where he would build it into a major international force in the book publishing industry. By 1971, Dick Bonnycastle had orchestrated the buyout of British publisher Mills & Boon and had contracted with Pocket Books and Simon & Schuster to distribute the Mills & Boon novels in the United States. In addition, he oversaw expansion to Australia in 1974, The Netherlands in 1975, set up a joint venture in 1976 in West Germany and in 1977 established a subsidiary in France. Dick Bonnycastle saw his company grow to where it would command eighty percent of the romance fiction market in North America. In late 1975, Toronto Star Ltd. purchased a 52.5 percent interest in Harlequin Enterprises and in 1981 acquired the balance of the company's shares. 
Dick Bonnycastle is currently chairman and president of his private investment company, Cavendish Investing Ltd.  Outside of the publishing world, in the 1980s Bonnycastle was one of the original Limited Partners of the first Oak Capital Partners, a venture capital company that provided the initial backing for Compaq Computer Corporation.  He has served as chairman of Bracknell Corporation (1983–90), Rupertsland Resources Ltd. (1975–83) and was a member of the board of directors of Western Feedlots Ltd. from 1970 to 1978 and of Torstar from 1975 to 1982.
A supporter of various causes related to nature and the environment, Bonnycastle is a trustee of the Fort Whyte Center for Environmental Education in Winnipeg, Manitoba. He has served as chairman of the Institute for Wetland and Waterfowl Research, an international affiliate of Ducks Unlimited on whose board his father had been a member, and in 1963 was one of the founders of the Canadian Parks and Wilderness Society. 
Dick Bonnycastle's great-great-great-grandfather, Darcy Boulton, was Canada's first racing steward. Bonnycastle became involved with the sport of Thoroughbred horse racing in the early 1970s. In 1973 he was one of the founding members of the board of stewards of the Jockey Club of Canada  and has served as its chairman since 2005. 
Bonnycastle and a cousin own a 20,000-acre (81 km2) ranch in Empress, Alberta. Racing under the name Harlequin Ranches at racetracks across Canada as well as in the United States, he has also campaigned horses in Europe. In the 1970s, one of his best runners in Canada was a multiple stakes-winning son of the great Northern Dancer named Nice Dancer. In 1978 Bonnycastle won the Classic 1,000 Guineas Stakes with Enstone Spark. In recent years, he was a partner in Mr Combustible who won the 2001 Chester Vase and Geoffrey Freer Stakes  and in Canada, his filly, Gold Strike, was voted the 2005 Canadian Champion 3-Year-Old Filly. Bonnycastle is a partner in Yankee Bravo who won the 2008 California Derby.
- [www.gov.mb.ca/chc/archives/hbca/biographical/b/bonnycastle_r.pdf Government of Manitoba Archives on the Bonnycastle family]
- Richard Bonnycastle Jr. at the NTRA
- Jensen, Margaret Ann. Love's $weet return: The Harlequin Story (1984) Popular Press ISBN 978-0-87972-318-7
- Montreal Gazette - August 13, 1977 article on Harlequin Enterprises
- August 28, 2007 Bloodhorse article on Dick Bonnycastle