The Marquette Building serves as a classic example of the First Chicago Style of architecture-a style that can be seen in buildings throughout the Loop and other buildings that were constructed throughout the city in the late 19th and early 20th century. These buildings feature terra cotta and other forms of masonry that cover steel-frame construction. The Marquette Building features a red terra cotta facade that has been slightly darkened over the years due to the acidity caused by air pollution.
The buildings of the Chicago Style also feature ornamental details throughout the first two or three floors of the building's exterior, as well as an ornamental cap on the building's top floor. These details can be seen when viewing the ornate cornice and features of the top floor and the lower two floors with the rest of the building. The most distinguishing feature of the First Chicago School, and one that is especially prominent in the Marquette Building, is the use of large horizontal plate-glass windows. For more information about the windows of the Marquette Building, please see the short video below.