Ivan Picelj (1924, Okucani, Croatia - 2011, Zagreb, Croatia) was a painter, printmaker, sculptor and designer. Studied at the Zagreb Academy from 1943 to 1946. 1950-1956 co-founded the Exat 51 group, together with fellow architects and painters. 1956 co-founded Industrial Design Studio (SIO). He showed his fascination with design and plastic thinking in 1948 while designing exhibition premises in Zagreb. Picelj was involved in the origins of the international movement, New Tendencies, 1961-1967, which promoted Zagreb as a centre of new European Constructivism and Op art. Worked a great deal with the Denise Rene Gallery, Paris. Picelj organized the first exhibition of industrial design in Zagreb in 1955. He did reliefs in wood and metal from 1957, structured of equal or close elements. He had his first one-man show in 1952 and since then he participated in numerous solo and group exhibitions all over the world. For his works he was awarded on several occasions in Croatia and abroad.
- Ivan Picelj, Zagreb: Galerija suvremene umjetnosti, 1966. (Croatian)
- Juraj Dobrović, Eugen Feller, Mladen Galić, Ante Kuduz, Ivan Picelj, Aleksandar Srnec, Miroslav Šutej, Belgrade: Muzej savremene umetnosti, 1968,  pp. With text by Ješa Denegri. (Serbo-Croatian)
- 3 reljefa / 3 Reliefs, Zagreb: Museum of Contemporary Art, 2001,  pp. (Croatian)/(English)
- Ivan Picelj iz Arhiva Toše Dabca / Ivan Picelj from The Tošo Dabac Archives, ed. Ivana Janković, Zagreb: Museum of Contemporary Art, 2014,  pp. Text by Marina Benažić. (Croatian)/(English)
- The Concrete Utopia. Ivan Picelj and New Tendencies 1961-1973, Lugano: Cortesi Gallery, 2016. Introduction.  (English)