Okla. Stat. tit. 74 § 5158
The Director of the Office of Management and Enterprise Services (OMES), in consultation with the responsible state agency, may retain or contract for the services of commercial appraisers, engineers, investment bankers, financial advisers, accounting experts and other consultants, independent contractors or providers of professional services as are necessary in the judgment of the Director to carry out the Director's powers and duties under this act. This may include the identification of public services and any related projects to be subject to invitations for qualifications or proposals under this act, the development of those invitations and related evaluation criteria, the evaluation of those invitations and the negotiation of any contract under this act.
Okla. Stat. tit. 74, § 5158