The Harold Washington Library Center is the central library for the Chicago Public Library System. It is located just south of the Loop 'L', at 400 S. State Street in Chicago, in the U.S. state of Illinois. It is a full-service library and is ADA compliant. As with all libraries in the Chicago Public Library system, it has free Wi-Fi internet service. Opened in 1991, it functionally replaced the city's 19th-century central library. The building contains approximately 756,000 sq ft (70,200 m2) of work space. The total square footage is approximately 972,000 sq ft (90,300 m2) including the rooftop winter-garden event space. It is named in honor of Mayor Harold Washington.

The Chicago Public Library (CPL) is the public library system that serves the City of Chicago in the U.S. state of Illinois. It consists of 81 locations, including a central library, three regional libraries, and branches distributed throughout the city's 77 Community Areas.