The Regional Transportation Authority (RTA) was created in 1974 upon the approval of a referendum by the residents of Cook, DuPage, Kane, Lake, McHenry and Will counties in northeastern Illinois. The RTA is a special purpose unit of local government and a municipal corporation of the state of Illinois. From the time of its creation, the RTA's mission has been to ensure financially sound, comprehensive and coordinated public transportation for northeastern Illinois.

In 1983, the RTA Act was amended with substantial changes made to the RTA's organization, funding and operations. The amended RTA Act created three "service boards" (the Chicago Transit Authority, or CTA, Metra commuter rail and Pace suburban bus) to handle all the transit system's operating and fare responsibilities.

The RTA's primary responsibility became financial and budget oversight of CTA, Metra and Pace. The RTA also was given responsibility for regional transit planning issues. The RTA's oversight responsibility is guided by the RTA's Board of Directors, who approve an annual budget and two-year financial plan. The Board consists of 12 members and a chairman appointed from the six-county region. The RTA Board also is required annually to review and approve a five-year capital plan, which is a blueprint of the capital activities to be funded by the RTA and executed by the CTA, Metra, and Pace.

CTA, Metra and Pace are each led by a Board of Directors which determine levels of service, fares and operational policies. The CTA is governed by the Chicago Transit Board whose seven members are appointed by the Mayor of Chicago and the governor. Metra's Board consists of seven members appointed by the region's county boards and the Mayor of Chicago. Pace is governed by a 12-member Board made up of current and former suburban village presidents and mayors.

The RTA is the second largest public transportation system in North America as measured by unlinked passenger trips and provides more than two million rides daily.  The combined assets of the RTA are valued at more than $27 billion and include 4,800 bus and rail cars plus 600 vanpool vehicles.  The system covers 7,200 route miles in the six-county region that currently has a population of approximately eight million people.