The Montana Department of Transportation (MDT) is a governmental agency in the U.S. state of Montana, responsible for numerous programs related to the construction, maintenance, and monitoring of Montana's transportation infrastructure and operations. While most of MDT's programs relate to the state's highway network, Montana's railroads and airports are also under the agency's purview. MDT received its current name in 1992; prior to that, the agency was known as the Montana Highway Department.