70 ILCS 1710/37
The Commission created by this Act shall cooperate with the Department of Commerce and Economic Opportunity , the units of government and with the plan commissions and regional planning commissions created by any unit of government and regional associations of municipalities within the area of operation of the Commission and any such plan commission, regional planning commission, regional association of municipalities or unit of government may furnish, sell or make available to the Commission created by this Act any of its data, charts, maps, reports or regulations relating to land use and development which the Commission may request.
The Commission created by this Act may cooperate with any planning agency in the State of Illinois, or with any planning agency of a sister State contiguous to the area of operation of the Commission to the end that plans for the development of urban areas in such sister State contiguous to the Metropolitan and Regional Counties Area may be integrated and coordinated so far as possible with the comprehensive and functional plans and policies adopted by the Commission.
70 ILCS 1710/37