N.C. GEN. STAT. §160A-460. Definitions
The words defined in this section shall have the meanings indicated when used in this Part:
(1) “Undertaking” means the joint exercise by two or more units of local government, or the contractual exercise by one unit for one or more other units, of any power, function, public enterprise, right, privilege, or immunity of local government.
(2) “Unit,” or “unit of local government” means a county, city, consolidated city-county, local board of education, sanitary district, facility authority created under Part 4 of this Article, special district created under Article 43 of Chapter 105 of the General Statutes, or other local political subdivision, authority, or agency of local government.
N.C. GEN. STAT. §160A-461. Interlocal cooperation authorized.
Any unit of local government in this State and any one or more other units of local government in this State or any other state (to the extent permitted by the laws of the other state) may enter into contracts or agreements with each other in order to execute any undertaking. The contracts and agreements shall be of reasonable duration, as determined by the participating units, and shall be ratified by resolution of the governing board of each unit spread upon its minutes.
N.C. GEN. STAT. §143 129. Procedure for letting of public contracts.
(e) Exceptions. – The requirements of this Article do not apply to:
(3) Purchases made through a competitive bidding group purchasing program, which is a formally organized program that offers competitively obtained purchasing services at discount prices to two or more public agencies.