In August 2017 the government of India published final fuel-efficiency standards for commercial heavy-duty vehicles. The standards are the government’s response to India’s rapidly growing commercial vehicle sector. Driven by economic growth, India’s diesel consumption has doubled in the past decade, increasing from 36.6 million metric tonnes in 2002 to 72.9 MMT in 2015. In India, HDVs account for a greater share of transportation petroleum end-use than in wealthier countries where passenger cars tend to dominate. The regulations are aimed at reducing fuel consumption and greenhouse-gas emissions from diesel-powered trucks and buses with a gross vehicle weight of 12 tonnes or greater. Indian HDVs greater than 12 tonnes represent about 60% of total fuel use and GHG emissions from the entire HDV fleet. The new standards include two phases of regulatory compliance. Phase 1 goes into effect April 1, 2018, while Phase 2 is effective beginning April 1, 2021. They apply to both vehicle manufacturers and importers. A conformity-of-production test will be undertaken by the Ministry of Road Transport and Highways once every two years.