In architecture, functionalism is the principle that buildings should be designed based solely on their purpose and function.
This principle is a matter of confusion and controversy within the profession, particularly in regard to modern architecture, as it is less self-evident than it first appears.
The theoretical articulation of functionalism in buildings can be traced back to the Vitruvian triad, where utilitas (variously translated as 'commodity', 'convenience', or 'utility') stands alongside firmitas (firmness) and venustas (beauty) as one of three classic goals of architecture. Functionalist views were typical of some Gothic Revival architects. In particular, Augustus Welby Pugin wrote that "there should be no features about a building which are not necessary for convenience, construction, or propriety" and "all ornament should consist of enrichment of the essential construction of the building".
The debate about functionalism and aesthetics is often framed as a mutually exclusive choice, when in fact there are architects, like Will Bruder, James Polshek and Ken Yeang, who attempt to satisfy all three Vitruvian goals.
In the wake of World War I, an international functionalist architecture movement emerged as part of the wave of Modernism. The ideas were largely inspired by the need to build a new and better world for the people, as broadly and strongly expressed by the social and political movements of Europe after the extremely devastating world war. In this respect, functionalist architecture is often linked with the ideas of socialism and modern humanism. A new slight addition to this new wave of functionalism was that not only should buildings and houses be designed around the purpose of functionality, architecture should also be used as a means to physically create a better world and a better life for people in the broadest sense. This new functionalist architecture had the strongest impact in Czechoslovakia, Germany, Poland, the USSR and the Netherlands, and from the 1930s also in Scandinavia and Finland.