Jefferson County Economic Dev 5217 Highway B Hillsboro, MO 63050 Phone : (636) 797-5336 Jefferson County Economic Dev Business Category Administration Of General Economic Programs Jefferson County Economic Dev 725 Maple St Hillsboro, MO 63050 Phone : (636) 797-5336 Business Category Government Offices-County Associations Fraternal Organizations Business Consulting Services County Government-Courts Courts Administration Of General Economic Programs Government Offices & Public Schools