Sidney Janis (July 8, 1896 – November 23, 1989) was a wealthy clothing manufacturer and art collector who opened an art gallery in New York in 1948. His gallery quickly gained prominence, for he not only exhibited the work of most of the emerging leaders of Abstract Expressionism, but also that of such important European artists as Pierre Bonnard, Paul Klee, Joan Miró, and Piet Mondrian.