The American Council of Engineering Companies of Illinois (ACEC-Illinois) is a statewide business association of engineering firms. The focus on business differentiates us from other design professional organizations that typically focus on professional licensure or technical issues. Our Members are the principals of engineering firms, including owners and managers.

ACEC-Illinois is overseen by a fifteen person Board of Directors, diversified by firm practice, location, size and ownership. It is administered by a professional staff, headquartered in its own building in Springfield, the State's Capitol.

ACEC-Illinois operates numerous programs in the interest of its Members, under the general categories of Business Practices, Government Affairs, Interassociation Liaisons, and Public Affairs. ACEC-Illinois is truly a volunteer-driven organization, with over 400 of its 900 principal members serving on over 30 committees. Through these programs, volunteer members and staff, ACEC-Illinois is able to provide representation, education and promotion of consulting engineering interests.