An office is generally a room or other area in which people work, but may also denote a position within an organization with specific duties attached to it (see officer, office-holder, official); the latter is in fact an earlier usage, office as place originally referring to the location of one's duty. When used as an adjective, the term "office" may refer to business-related tasks. In legal writing, a company or organization has offices in any place that it has an official presence, even if that presence consists of, for example, a storage silo rather than an office.

An office is an architectural and design phenomenon and a social phenomenon, whether it is a small office such as a bench in the corner of a small business of extremely small size (see small office/home office) through entire floors of buildings up to and including massive buildings dedicated entirely to one company. In modern terms an office usually refers to the location where white-collar workers are employed.

The structure and shape of the office is impacted by both management thought as well as construction materials and may or may not have walls or barriers . The word stems from the Latin officium, and its equivalents in various, mainly romance, languages. Interestingly, this was not necessarily a place, but rather an often mobile 'bureau' in the sense of a human staff or even the abstract notion of a formal position, such as a magistrature. The relatively elaborate Roman bureaucracy would not be equaled for centuries in the West after the fall of Rome, even partially reverting to illiteracy, while the East preserved a more sophisticated administrative culture, both under Byzantium and under Islam.

The Rayburn House Office Building (RHOB) is a congressional office building for the U.S. House of Representatives in the Capitol Hill neighborhood of Washington, D.C., between South Capitol Street and First Street.

Rayburn is named after former Speaker of the House Sam Rayburn. It was completed in 1965 and at 2.375 million square feet (220,644 m²) is the largest congressional office building and the newest House office building (the only newer congressional office building is the Hart Senate Office Building, completed in 1982.)

Rayburn was completed in early 1965 and is home to the offices of 169 Representatives.

Earlier efforts to provide space for the House of Representatives had included the construction of the Cannon House Office Building and the Longworth House Office Building. In March 1955, House Speaker Sam Rayburn introduced an amendment for a third House office building, although no site had been identified, no architectural study had been done, and no plans prepared.

The area west of the Longworth Building on squares 635 and 636 was chosen, with the main entrance on Independence Avenue and garage and pedestrian entrances on South Capitol Street, C Street, and First Street Southwest. The cornerstone was laid in May 1962, and full occupancy began in February 1965.