In design, functionalism is the concept that objects or buildings should be planned in accordance with their actual uses, rather than for the sake of appearance. In a functional design the utilitarian requirements of a building or an object are not concealed by ornamentation. The modern practice is to keep the decoration a secondary factor and to make it-harmonize with the uses of the object or structure. To a large extent, modern architecture and the design of modern furniture and other objects are based on the principles of functionalism.
The well-known functionalist motto "Form follows function" was originated by the late -19th-century architect Louis Sullivan. His approach was adopted and further developed by his student Frank Lloyd Wright and by such noted architects as Ludwig Mies van der Rohe, Walter Gropius, and Le Corbusier. Each has designed buildings of great geometric simplicity that integrate function with appearance.