Clarence Howard Blackall (February 3, 1857 – March 5, 1942) was an American architect who is estimated to have designed 300 theatres.

[2] He designed the 1894 Carter Winthrop Building, which was the first steel frame structure in the city of Boston.

[3] In addition to its innovative technology, the structure also used terra cotta trim and featured a dramatic, deep, and overhanging cornice.

Blackall is also credited with designing the Copley Plaza Hotel, the Foellinger Auditorium (1907) on the University of Illinois campus, as well as the Little Building (1917)[4] at Emerson College on the site of the Pelham Hotel (1857), the "first apartment house in any city along the Atlantic seaboard of the United States" according to architectural historian Walter Muir Whitehill.

[5] It was also the first of Blackall's theatres to use a large steel girder to support the balcony, eliminating the need for architectural columns.