Peter Lancelot Williams (1914–1995) was an English designer and dance critic. He founded and edited the monthly magazine Dance and Dancers for thirty years, wrote columns for national newspapers and was an influential chairman of various committees and trusts.
Williams was born on 12 June 1914 in Burton Joyce, a village near Nottingham. He was the son of Godfrey Williams, an army officer from a Cornish family who had been a Major in the 11th Hussars. At the age of seven, he saw Diaghilev's production of The Sleeping Beauty at the London Coliseum. This impressed him greatly and he became a regular ballet-goer and fan of the ballerina Olga Spessivtseva.
He was educated at the famous Harrow School in north west London. He then studied design at the Central School of Arts and Crafts and, after graduating, established his own fashion design business in Ebury Street in 1934. This closed on the outbreak of World War II in 1939. His wartime service was as a transport officer in the family home in Cornwall at Perranarworthal. After the war, he became head designer at the UK subsidiary of the large swimwear company Jantzen.
In 1947, he executed his first costume sketches for Designs with Strings, a ballet being created by American choreographer John Taras for the Metropolitan Ballet, a short-lived, London-based company. He then designed for Michel Fokine's Prince Igor, also by the Metropolitan Ballet. For the Sadler's Wells Theatre Ballet, he did designs and the libretto for Andrée Howard's Selina.