Hydrogen fueled fuel cell vehicles (FCVs) will play a major role as a part of the change toward the hydrogen based energy system. When combined with the right source of energy, fuel cells have the highest potential efficiencies and lowest potential emissions of any vehicular power source. As a result, extensive work into the development of hydrogen fueled FCVs is taking place. The aim of this paper is to highlight some of the research and development work which has occurred in the past five years on fuel cell vehicle technology, with a focus on economic and environmental concerns. It is observed that the current efforts are divided up into several parts. The performance, durability, and cost of fuel cell technology continue to be improved, and some fuel cells are currently ready to be mounted on vehicles and tested. Environmental and economic assessments of the entire hydrogen supply chain, including fuel cell end-use, are being carried out by groups of researchers around the world. It is currently believed that fuel cells need at least five more years of testing and improvement before large scale commercialization can begin. Economic and environmental analyses show that FCVs will likely be both economically competitive and environmentally benign. Indeed, the transition of the transportation sector to the use of hydrogen FCVs will represent one of the biggest steps toward the hydrogen economy. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.