Soon after the war in 1945, the United States Congress passed the Legislative Reorganization Act of 1946, in order to modernize and streamline its operations and provide senators and committees with professional staff assistance.

Bronze spandrels between the third- and fourth-floor windows depicted scenes from American industry: Shipping, Farming, Manufacturing, Mining and Lumbering.

By then, increased costs of construction caused some scaling back of the original architects' design, including the elimination of a planned central corridor.

The Dirksen Building was designed to accommodate the new modern invention of television and the wider media era, complete with committee hearing rooms equipped with rostrums that were better suited to listening to testimony than sitting around conference tables, as had been done in previous committee rooms, both in the U.S. Capitol and the Russell Senate Office Building, during the 19th and earlier 20th centuries.

A revolving support fund administered by the U.S. Department of the Treasury for the office of the Architect of the Capitol to run the exercise / health facility was established in Chapter 4, Section 121f of the Title 2 of the United States Code.