Section 30 ILCS 500/25-15 - Method of source selection(a) Competitive sealed bidding. Except as provided in subsection (b) and Sections 20-20, 20-25, and 20-30, all State contracts for supplies and services shall be awarded by competitive sealed bidding in accordance with Section 20-10.(b) Other methods. The chief procurement officer may establish by rule (i) categories of purchases, including non-governmental joint purchases, that may be made without competitive sealed bidding and (ii) the most competitive alternate method of source selection that shall be used for each category of purchase.Added by P.A. 90-572,§ 25-15, eff. date - see§ 99-5.