The Reliance Building is a skyscraper located at 1 W. Washington Street in the Loop community area of Chicago, Illinois. The first floor and basement were designed by John Root of the Burnham and Root architectural firm in 1890, with the rest of the building completed by Charles B. Atwood in 1895. It is the first skyscraper to have large plate glass windows make up the majority of its surface area, foreshadowing a design feature that would become dominant in the 20th century.