Purpose: This regulation sets forth authority, policy, and responsibilities of the HQUSACE Transportation Systems Mandatory Center of Expertise (TSMCX). The TSMCX is established to support engineering, planning, design, construction, evaluation, criteria development, and real property requirements for all military transportation systems. Transportation systems include airfields; railroads; roads; streets; ports; non-organizational parking; organizational vehicle parking; special vehicle guideways, and roadways; and all facilities directly in support of transportation vehicles.