Bridget Riley (born 1931, London) is a British painter and a central figure of the Op Art movement. She is best known for her precise abstract compositions—initially in black and white, later in color—whose lines, curves, and repeated forms generate powerful sensations of movement, rhythm, and optical vibration.

Riley trained at Goldsmiths College from 1949 to 1952 and then at the Royal College of Art until 1955. She held her first solo exhibition at Gallery One in London in 1962, and three years later her paintings featured in The Responsive Eye at the Museum of Modern Art in New York. In 1968 she won the International Prize for painting at the Venice Biennale, becoming the first woman and the first British contemporary painter to receive it. Her later honors include the Praemium Imperiale (2003), the Goslar Kaiser Ring (2009) and the Rubens Prize of the city of Siegen (2012). Major surveys of her work have taken place at the Hayward Gallery (1971), Tate Britain (2003) and, in 2019, the Scottish National Gallery in Edinburgh and the Hayward Gallery. That same year the National Gallery in London unveiled Messengers, a large wall painting made for the museum. Her paintings are held by MoMA, Tate and the Metropolitan Museum of Art, and she works in London, Cornwall and France.