British painter and printmaker, born in Birmingham. He studied at Birmingham College of Art, 1955–60, then at the Académie de la Grande Chaumière, Paris, 1960–61. Although predominantly abstract, much of his work invokes ambiguous effects of space and volume. Study (1965, Tate) is on the scale of the *Post-Painterly work current at the time, but, in contrast to the flatness and brilliant hues cultivated by such work, it makes use of pictorial illusionism (the surface appears to fold open) and an earth-based colour scheme. Walker also makes self-conscious references to art history. The Juggernaut series of the early 1970s suggests the accumulations of jagged planes in *Cubist collage, while the Numinous series of 1977–8 was within a tradition of balcony paintings by Goya, Manet, and *Matisse.