Between 1943 -1946, Ivan Picelj (1924 - 2011) studied at the Academy of Fine Arts in Zagreb. He was one of the founders of EXAT-51 (1951) and the Studio of Industrial Design (SIO, 1956). Picelj organized the first exhibition of industrial design in Zagreb in 1955. He developed a specific, impersonal direction of geometric abstraction in Croatian art. His aesthetics originated from general principles of constructivism. He was involved in the development and expansion of the international movement New Tendencies (1961 -1967), within which he created a series of programmed works exploring visual perception, mathematical rhythms, and movements of particles (programmed case of 8-1 cm, 1966). One of his basic methods was multiplication of a basic plastic unit within the regular raster surface. Since 1957 he exhibited sculptures, reliefs in wood and objects in metal. His graphic design (posters, books and equipment), during the mid-sixties significantly enhanced the visual culture of graphic design. Picelj designed pavilions for Yugoslav exhibitions at home and abroad. (See the book EXAT-51 pp. 224). His first solo exhibition was organized in 1952 and since then he participated in numerous solo and group exhibitions around the world. Picelj worked intensively with Denis Rene Gallery in Paris. His work received awards several times at home and abroad.