1945: In 1945, the Chamber successfully advocated the State Slum Clearance and Rehousing Program Act, and passed its own Modernized Building Code. It was presented to the City Council for adoption. The Association also paved the way for Chicago's great housing developments following World War II.

Chicago's many new parking garages and parking lots erected since 1949 are a direct result of a Parking Plan for the City of Chicago, which the Chamber and the State Street Council jointly conceived and financed.

1950: The Chamber conducted a successful Chicagoland Fair, Commerce and Industry Exposition in 1957, and an even more successful Chicago International Trade Fair of 1959 followed it. The latter brought Her Majesty, Elizabeth, Queen of the British Commonwealth, to Chicago as well as a giant U.S. Naval Flotilla. The trade fair added millions of dollars to 1959 Chicago business totals.

1960: Throughout the 1960's, Chamber activities included important studies designed to develop programs and to initiate actions. One study was aimed at finding a solution to the area's mass transportation problems; another to determine the area's export and import potential; a third to discover the coming impact of waterway developments; a fourth designed to produce housing in Chicago for middle-income families; a fifth designed to ascertain the area's future banking requirements; a sixth concerned with diversion of water from Lake Michigan - a matter of enormous consequence to every area resident; and a seventh concerned with the revitalization of our older business communities.

In 1963, the Chamber participated in the highly successful Illinois Trade Mission to Europe conducted by the Illinois Committee for Trade Expansion to increase Illinois export activity and to point out the advantages of using Chicago's shipping facilities and promote tourism to the area.

1965: Mayor Richard J. Daley presented the Chamber with a 1965 Human Relations Commission Award for, "initiating and successfully carrying out unique programs with the business community to open up more and better job opportunities for minority group people."

In 1966, the Chamber's Research and Development Council played a prominent part in attracting the $395 million atom accelerator at Weston (decision made by the Atomic Energy Commission). Also, a College Career Conference brought 1,800 college students from all over the nation with representatives of 128 major Chicago area employers to discuss the challenging business opportunities available in the Chicagoland area. This conference is the biggest event of its kind in the United States.

In addition, prominent business leaders began organizing Youth Motivation Program events in high schools. The Chamber took over operations in 1973 and added a scholarship component. This program was under the Chamber’s control until 2001, when the activities were spun off to dedicated youth service organizations.

The Japan Midwest Association was formed with membership listing the heads of major Chicago, Midwest and Japanese business firms in 1967. The Chamber and the Japan Committee for Economic Development formed the Association. The Chamber also initiated an on-the-job training program for member companies in cooperation with the Chicago Committee on Urban Opportunity. That same year, the Chamber sponsored two conferences that brought national and international attention to the city. A forum for experts in foreign trade and investment, marketing and transportation was provided by the conference on Chicago's Growth as an International Center. The first annual National Symposium on Measuring the Investment Performance of Pension and Profit Sharing Funds attracted financial experts from 25 states to the Chicagoland area.

In 1968, the Chamber participated in a yearlong civic effort culminating in passage on the November ballot of a proposal to call a State constitutional convention.

1969 saw growing congestion from the increased volume of freight and numbers of people being transported caused the Chamber to launch a regional audit of transportation planning to be sure that maximum efficiency and coordination would result in a metropolitan area master plan embracing all modes of transportation.

1970: The Chicago Board of Education asked the Chamber to undertake an extensive study of its (CBE) management practices to investigate cost reduction opportunities in its $733 million budget in 1971.

In 1973, the first export fair ever held in the United States was sponsored by the Chamber (November) in cooperation with the Japan Midwest Association and other Japanese government and business organizations. It was the largest U.S. export promotion ever held anywhere and attracted more than 400 exhibitors and hundreds of buyers from Japan.