Michael Craig-Martin is one of the key figures in the first generation of British conceptual artists. Particularly affected by Minimalism, his early work made deliberate reference to the American artists he most admired, such as Donald Judd, Jasper Johns, and Robert Morris. Craig-Martin often uses ordinary household materials in his sculptures, playing against the logic of his sources. In the early 1970s, he first exhibited his now seminal work An Oak Tree (1973) consisting of a glass of water standing on a shelf attached to the gallery wall. In the accompanying text, he asked himself questions to assert that the glass was in fact an oak tree. Craig-Martin continued working in various forms, always maintaining an elegant restraint and conceptual clarity.