Since the fuel economy and GHG regulations for MHDVs are new, it is important to establish methods and processes that will serve both industry and government in the coming decades. Some sources of information already exist, such as information on bills of lading, fuel purchases, and road use taxes. All such sources of information should be investigated for possible use on an ongoing basis for tracking items of interest to these regulations and their cost and their effectiveness. New sources of information are coming online. Federal and state governments have regulations requiring the reporting of numerous items that can be used for creating a baseline and regularly tracking the improvement in the industry in fuel usage and ton-miles. This includes hours of service, inspection reports, bills of lading, weigh station inspections, and fuel tax reporting. In the near future, the Federal Motor Carrier Safety Administration is expected to mandate the use of recorders for drivers’ hours of service. These could become excellent sources for tracking information on the vehicles. California has a rule for electronic trailer refrigeration units that includes a telematics monitor requirement. Also, as mentioned in Chapter 2, the EPA SmartWay program is another source for fuel consumption information from participating fleets. As NHTSA deliberates on potential rules and regulations for V2X (Vehicle to Vehicle, Vehicle to Infrastructure), the regulatory instrument could be crafted to provide new sources of information on fuel use and GHG emissions. EPA and NHTSA should establish a plan for obtaining information in the future that takes account of all public, private, and governmental sources of information.