Haw. Rev. Stat. § 103D-802: Cooperative purchasing authorized.

A public procurement unit may either participate in, sponsor, conduct, or administer a cooperative purchasing agreement for the procurement of goods, services, or construction with one or more public procurement units, external procurement units, or nonprofit private procurement units pursuant to rules adopted by the policy board and an agreement entered into between the participants. The cooperative purchasing may include, but shall not be limited to, joint or multi-party contracts between public procurement units, and state public procurement unit requirements contracts which are made available to local public procurement units. Cooperative purchasing agreements may be exempt from preferences pursuant to part X.