SDCL § 11-2-5: Joint planning by counties--Sharing of expenses--Objectives of joint planning.

The boards of two or more county commissioners may direct their planning commissions to plan jointly. Expenses incurred in connection with joint planning, including but not limited to contracted services, shall be shared equitably among the counties involved. Encouraging regional economic development, including but not limited to the creation of compatible controls in neighboring counties, shall be the objective of joint planning.