70 ILCS 507/35
In order to implement the intergovernmental agreement or any redevelopment plan, land development, or project approved by the Commission, members of the Commission and the Commission shall have the authority to enter into additional intergovernmental agreements among and between themselves; provided, however, that no additional intergovernmental agreement shall take effect unless executed, or otherwise consented to, by all of the members of the Commission. The agreements may, notwithstanding any statutory limitation or the absence of any other specific statutory authority, provide for: (i) the joint exercise, combination, or transfer of any power or function among or between any of the contracting parties; (ii) the performance, by any one or more of the contracting parties, of any service, activity, or undertaking that any of the contracting parties is authorized to perform; and (iii) the limitation or restriction of the exercise of any power or function, or the performance of any service, activity, or undertaking, by any of the contracting parties; provided, however, that no such agreement shall empower the Commission to exercise directly either zoning or taxing powers not expressly authorized by this Act.
70 ILCS 507/35