Karel Appel is a Dutch painter and sculptor who lived and worked in Paris. In 1948, Karel Appel participated, with Corneille and Constant, in an experimental group, which would reject geometric abstraction, a major artistic trend of that period. Karel Appel then joined the CoBrA movement, which brought together artists from Copenhagen, Brussels and Amsterdam. It advocated the rejection of rationalism and geometry. Karel Appel expressed himself spontaneously, intuitively and violently, without necessarily referring to reality. His work joins the figurative, primitive, and childish expressionism whose strong colours are sometimes considered provocative. Karel Appel explored many techniques including lithography, and signed several prints with Pierre Alechinsky, one of the common denominators of these two artists being the CoBrA movement.