Idaho Code § 39-3130: Reciprocal agreements between states to share services.

In such regions where natural population groupings overlap state boundaries, an interstate regional behavioral health service may be established jointly with a neighboring state or states. In such instances, the state behavioral health authority may enter into reciprocal agreements with these states to either share the expenses of the service in proportion to the population served; to allow neighboring states to buy services from Idaho; or to allow Idaho to purchase services that are otherwise not available to its citizens.