The Office of the Architect of the Capitol provides facilities and meets space needs for the Illinois General Assembly and its supporting commissions and bureaus. The commission's goal is to provide a more functional facility with flexible and efficient space utilization resulting in effective processes and procedures.
    The commission reviews and approves all contracts for the repair, rehabilitation, construction or alteration of all state buildings in the Springfield Capitol Complex, including tunnels, power and heating plants and surrounding grounds. In regard to areas of the Capitol and the William G. Stratton Building that are being rehabilitated, the commission correlates the House and Senate leadership's ideas with the needs and wants of the members and relays them to the architect. It also devised the Master Space Allocation Plan showing where all functions of the General Assembly, the supporting commissions and bureaus, and the executive offices in the Capitol Building will be located. The commission plans office layouts for General Assembly members, and also is responsible for purchasing for the State of Illinois, ground and buildings in the area of Springfield bounded by Third, Cook, Pasfield and Washington Streets.