While the transport sector currently accounts for around 28% of total global energy use, it is estimated that this may more than double by 2040 as a result of projected increases in the number of light-duty vehicles and associated fuel consumption. Importantly, heavy-duty vehicles (HDVs) only make up 11% of the global vehicle fleet, yet currently account for 46% of vehicular carbon dioxide emissions and 71% of vehicular particulate emissions IPEEC’s current work in this sector focuses on addressing untapped energy efficiency potential by helping participating countries better develop stronger policies and implementation approaches.