Michael Craig-Martin (1941) was born in Dublin, but moved to Washington with his family. He trained at the Yale School of Art and Architecture (1966), where he was influenced by the colour theories of Josef Albers. He worked as a teacher at Goldsmith College School of Art (London) and tutored artists who would go on to become well-known figures, such as Damien Hirst, Gary Hume and Sarah Lucas, among others. His work includes An Oak Tree (1973), in which he explores the conceptual.