High-tech architecture, also known as Late Modernism or Structural Expressionism, is an architectural style that emerged in the 1970s, incorporating elements of high-tech industry and technology into building design. High-tech architecture appeared as a revamped modernism, an extension of those previous ideas helped by even more technological advances. This category serves as a bridge between modernism and post-modernism, however there remain gray areas as to where one category ends and the other begins. In the 1980s, high-tech architecture became more difficult to distinguish from post-modern architecture. Many of its themes and ideas were absorbed into the language of the post-modern architectural schools.

Like Brutalism, Structural Expressionist buildings reveal their structure on the outside as well as the inside, but with visual emphasis placed on the internal steel and/or concrete skeletal structure as opposed to exterior concrete walls. In buildings such as the Pompidou Centre, this idea of revealed structure is taken to the extreme, with apparently structural components serving little or no structural role. In this case, the use of "structural" steel is a stylistic or aesthetic matter.

The style's premier practitioners include the British architects Sir Norman Foster, Sir Richard Rogers, Sir Michael Hopkins, Italian architect Renzo Piano and Spanish architect Santiago Calatrava, known for his organic, skeleton-like designs. Early High Tech buildings were referred to by historian Reyner Banham as "serviced sheds" due to their additional exposure of mechanical services in addition to the structure. Most of these early examples used exposed structural steel as their material of choice. As hollow structural sections had only become widely available in the early 1970s, we see much experimentation with this material.