The Federal Surface Transportation Assistance Act of 1973 required the formation of Metropolitan Planning Organizations (MPO) for urban areas with a population greater than 50,000.  MPOs were created in order to ensure existing and future expenditures for transportation projects and programs were based on a comprehensive, cooperative, and continuing planning process.  Federal funding for transportation projects and programs are channeled through this planning process.  

 The geographic boundary for the Rapid city Area Metropolitan Planning Organization includes the City of Rapid City, the City of Box Elder, the City of Summerset, City of Piedmont, Ellsworth Air Force Base, the unincorporated areas of Black Hawk and the developing areas of Pennington County and Meade County.  This includes the existing urbanized area and the area which is projected to become urbanized within the twenty year horizon of the Long Range Transportation Plan.  The population within the transportation planning area is approximately 93,000 people according to the 200 Census.

The MPO carries out transportation planning efforts mandated by the United States Department of Transportation.  This process has secured millions of dollars toward the development of the transportation infrastructure for the Rapid City area.