Lever House is a 24-story glass and stainless steel clad office building composed of a vertical slab rising above a horizontal base. Its construction in 1950-52 heralded the beginning of a new wave of American skyscraper construction and a new synthesis of modernist architectural ideals. Since the time of its completion, its crystalline forms and glazed curtain walls have attracted world attention. It has assumed a major role in the literature of modern architecture and has been widely recognized as a key monument in the evolution of the International style.