Reginald Sherriff Summerhays was a British equestrian and writer.

In 1914, he was appointed by the British War Office as a Civilian Remount Purchasing Officer, with the duty of purchasing horses for World War I. Later he served as part of the Army Service Corps. In the early 1920s, he rode in the three horse endurance tests of 60 miles (97 kilometres) a day for five consecutive days.^{[clarification needed]} He then became Managing Director of one of the largest hunting, hacking and pony establishments in the country.^[which?] Later he became editor of the journal Riding, retiring after thirteen years. It was then he published the first of his equine titles.^[1]

For over 40 years, Summerhays was a horse show judge as well as serving on the boards of many horse breeding societies. He was also president of the Arab Horse Society. His interests included polo. He was the originator of the Horseman's Sunday and also of the Horse and Pony Breeding and Benefit Fund.^[2]

• Here's Horse Sense
• From Saddle to Fireside
• Elements of Riding^[3]
• Elements of Hunting
• Riding For All
• Observer's Book of Horses and Ponies
• The Problem Horse
• It's A Good Life With Horses
• Summerhays' Encyclopedia for Horsemen^[4]
• Our Horses Horses and Ponies
• Riding on a Small Income
• The Story of the International
• The Young Rider's Guide to the Horse World
• A Lifetime with Horses
• Arabian Horse in Great Britain (1967), London, Country Life Ltd.^[5]
• The Arabian Horse (1974) A.S. Barnes, ISBN 0-498-07474-9, ISBN 978-0-498-07474-5
• In Praise of the Arabian Horse (1954) coauthor with Staveacre F. W. F. The Arab Horse Society & J A Allen ASIN: B000WI33ZY
• The Courthouse Arabian Stud (1966) H.V. Musgrave Clark; Rev edition