The Senate President's office is within a suite of rooms of the later nineteenth-century Brigham extension. From 1898 it served as the Senate Reading Room and library for members until it was adopted as the ceremonial office of the Senate President in 1970. Also within the suite are the president's small private office, the former Senate Clerk's office, and the Coolidge Room, a small office that was used by Calvin Coolidge during his term as president, and which has been preserved intact.
The President's Office was decorated according to the specifications of Charles Brigham in 1896; during the 1988 restoration, investigative paint analyses revealed stenciled patterns in olive and mustard colors in the ceiling cove. The ceiling is decorated with ornate plaster work, and the carved doors fitted with stained glass transoms. The lower half of the room is paneled and fitted with built-in cabinetry of white mahogany, all of which is finely carved. Egg-and-dart molding, broken scroll pediments, fluted pilasters, and wreaths and swags—all references to the neo-classical Bulfinch capitol—are teamed with floral and foliate decoration, creating richly patterned vistas throughout.
The A. H. Davenport Company supplied much of the woodwork and furniture for the suite. The carpet was installed in 1988 and is a reproduction of the original.