Throughout its history, the library's technology resources attracted a large clientele from Chicago-area business and industry. Its equally outstanding collections of historical and rare materials drew scholars from many countries. To assist the post–World War II expansion in scientific research, the directors established an innovative fee-based research service for industry and government. Since 1951, the collection has been limited to current science, technology, and medicine.
The Crerar Library opened in the Marshall Field building, moving in 1921 to its own building at the northwest corner of Randolph Street and Michigan Avenue. The Board of Directors of the library established a building fund with the 1889 endowment and set out to gain approval for a Grant Park location. In 1902, the Chicago City Council approved the plan, but public criticism force the design to be built on the Northwest corner of Michigan Avenue. World War I postponed groundbreaking of the 16-story Holabird & Roche design until 1919. The building became overcrowded in the 1950s, and because the library's endowment income no longer covered operations, the directors contracted with the Illinois Institute of Technology to provide library services. In 1962, the library moved into a new building was designed by architect Walter Netsch. It was a facility with a pleasing modern aesthetic inspired by Mies van der Rohe. By the mid-1970s, however, the facility had become inadequate and in 1980 Crerar and IIT agreed to terminate the contract within four years. The directors consolidated the collection with the University of Chicago's science collection in a new building, which opened in September 1984. The merger, among the largest in American library history, resulted in a collection of 900,000 volumes.
The Foundation now also sponsors the John Crerar Foundation Science Writing Prize for College students.