International Style was an aspect of Modernism developed in Europe and the United States in the 1920s and 1930s.
Henry-Russell Hitchcock and Philip Johnson helped to define the three principles of Modernism, namely, conveying volume rather than mass, balance rather than symmetry, and the absence of applied ornament. International Style's basic elements were rectilinear forms, open interior spaces, large expanses of glass, steel, chrome, plastic, and reinforced-concrete, and light, unadorned surfaces.
Ludwig Mies van der Rohe (and his Villa Tugendhat and Barcelona chairs,) Le Corbusier and Walter Gropius of the Bauhaus school most notably employed these features. Office buildings of multinational corporations also widely employed International Style architecture and interior design in the decades after the Second World War.