Percy Richard Morley Horder (18 November 1870 – 7 October 1944) was an English architect who early in his career worked from offices in Stroud and later in London. His early work was in the Arts and Crafts style, but after the First World War his buildings were increasingly in the Neo-Georgian fashion. His work included public houses for the Godsell Brewery and designing new country houses or partially rebuilding existing houses. He also designed country-house gardens and is noted for laying out Highfields Park, Nottingham together with the adjacent Nottingham University Campus. He undertook architectural work in many parts of the British Isles including Ireland. He is probably best remembered for the Trent Building in the University of Nottingham. and for design of the London School of Hygiene and Tropical Medicine. His work at Upton House, Warwickshire for Viscount Bearsted is notable, but it is his work for Jesse Boot, both the Boots the Chemists stores, but most importantly the Trent Building and the laying out the campuses of the University of Nottingham, which influenced design at other English universities, for which he must take the greatest credit.

He was born in Torquay, the son of the Congregationalist minister William Garrett Horder but later the family moved to Tottenham, London. He married Rosa Catherine (Katie) Apperly in 1897, the only daughter of Ebeneezer Apperley, a Stroud, Gloucestershire cloth manufacturer. The Horder family lived at 6 (now 18) Hamilton Terrace, St John's Wood and their daughter Barbara Morley Horder (1898–1986) became a noted actress.

In 1927 Morley Horder acquired the Court House at East Meon in Hampshire. This was a country residence of the bishops of Winchester. It was in a badly dilapidated state and he set about restoring the building. Of this residence, the great hall, a solar, and a garderobe block survive largely intact. The Court House is remarkable for its fine state of preservation. It was commissioned by the bishop, William of Wykeham and built by his master mason William Wynford, one of the greatest of 14th-century architects, who remodelled the nave of Winchester Cathedral and designed Winchester College and New College, Oxford. Morley Horder added a north wing, joining the medieval house to the 18th-century thatched cottage on the roadside, and he laid out the gardens between the house and the 18th-century thatched barn on what had become a farmyard. Morley Horder also bought and restored a number of thatched cottages in the village. An account of Morley Horder's restoration work is given in a Country Life article.

Horder appears to have been eccentric, with a domineering character: "To his pupils he was "Holy Murder" (a Spoonerism on his name); according to his daughter, "he was most charming... and most awful"... "pushing artistic temperament to its limits, [he] looked and behaved like a cantankerous Old Testament prophet."

Ard Na Sidhe Country House, Carragh Lake, Killorglin, Co. Kerry, Ireland (1913) https://www.ardnasidhe.com/history

Morley Horder worked with the Labour politician and landowner Sir Stafford Cripps and the local stonemason George Swynford on the provision of council housing in the village of Filkins. Cripps insisted that the new buildings should be of stone and stylistically in keeping with local vernacular traditions, meeting the difference in cost for the council housing, re-opening quarries on his own land to provide building. This was recorded in Country Life. As a result, by 1944 Filkins was being hailed as 'a modernised village' and 'an illustration of contemporary village planning', in an article in Country Life by Christopher Hussey.

Through his friendship with Sir Jesse Boot he obtained the commission to design the buildings at University College, Nottingham from 1922 to 1928. This included the Highfields Park, the Highfields Lido and the Trent Building.

Also: Derby, corner of St Peter's Street and East Street - built 1912 and featuring statuary and pargetting. Not occupied by Boots since the mid-1970s.