William M. Kendall of the architectural firm McKim, Mead & White designed the Municipal Building. Two of the firm's other partners, Burt L. Fenner and Teunis J. van der Bent, were tasked with leading construction, while the city's Department of Bridges supervised the project. Alexander Johnson was chief engineer, Purdy and Henderson were consulting engineers, and the Thompson–Starrett Company was the general contractor. The Mount Waldo Construction Company provided the granite, while Robert Wetherill & Co. installed the original elevators. The foundations were dug by the Foundation Company.