One of Mondrian's most iconic Neo-Plastic compositions, featuring a dominant large red rectangle balanced asymmetrically against smaller fields of blue, yellow, and white, all delineated by the artist's characteristic bold black grid lines. This masterpiece epitomizes De Stijl principles of universal harmony through the reduction of form to primary colors and orthogonal geometry. Held in the Kunsthaus Zürich, it remains a touchstone of 20th-century abstraction.