The Old New York County Courthouse, better known as Tweed Courthouse, is the legacy of Tammany Hall boss William M. Tweed, who controlled the initial construction. Built over a period of twenty years, between 1861 and 1881, it is the product of two of New York`s most prominent nineteenth-century architects, John Kellum and Leopold Eidlitz. Grandly scaled and richly decorated, the courthouse retains its original spatial arrangement, including thirty monumental courtrooms and a five-story central rotunda. Under an accelerated time schedule, John G. Waite Associates, Architects (JGWA) restored a neglected, deteriorated 177,500 square foot courthouse for use by the New York City Department of Education. Recognizing the significance of the historic Tweed Courthouse, JGWA lobbied for its restoration and the responsible use of its interior spaces. JGWA worked with multiple civic entities throughout the restoration process to insure the project ran smoothly. An on-site office was created to expedite the design and construction process. As the first step in the restoration process, JGWA prepared a comprehensive feasibility study for the exterior and interior spaces, documenting existing conditions and recommending procedures for restoration. Utilizing recommendations from the study, the firm applied their profound knowledge of materials conservation and restoration and of nineteenth-century mechanical and structural systems, installing new lighting, security, HVAC, and fire system with only minimal intrusions on the historic spaces.