70 ILCS 1710/3
As used in this Act, unless the context otherwise requires, the following terms have the following meanings:
"Metropolitan and Regional Counties Area" and "Area of operation" mean and include all of the territory of the State of Illinois contained within the counties of Washington, Bond, Madison, St. Clair, Randolph, Clinton, and Monroe;
"Commission" means the Southwestern Illinois Metropolitan and Regional Planning Commission created by this Act;
"Unit of government" means any county, body politic, municipality, township, special district, unit of local government, school district, any Illinois or United States agency, any political subdivision of another State, and the State of Illinois;
"Person" includes an individual, partnership, firm, public or private corporation and unit of government.
70 ILCS 1710/3