65 ILCS 5/11-39.2-40

The municipality may award the contract to the highest overall ranked design-build entity. Notice of award must be made in writing. Unsuccessful design-build entities must also be notified in writing. The municipality may not request a best and final offer after the receipt of proposals of all qualified design-build entities. The municipality may negotiate with the selected design-build entity after award, but prior to contract execution, for the purpose of securing better terms than originally proposed if the salient features of the request for proposal are not diminished. A design-build entity and associated design professionals must conduct themselves in accordance with the relevant laws of this State and the related provisions of the Illinois Administrative Code.