Taking advantage of the multi-fuel ability of internal combustion engines, mixtures of hydrogen and methane as fuel allow a substantial reduction of CO2-emissions at affordable costs. By means of a prototype vehicle that was adapted for the operation with mixtures of methane and hydrogen and approved for road traffic, necessary technical adjustments and safety measures for gas-powered vehicles are explained. Synergies in production, storage, distribution, and combustion of mixtures of hydrogen and methane in terms of technical specifications, safety, regulations, and infrastructure are analyzed. In the EU blends of hydrogen and methane are seen as an interesting option to reduce emissions in vehicle traffic. Legislation is updated to include these blends. A survey of international regulations and standards for gas-powered vehicles is given, addressing issues of type-approval, fuel consumption and pollutant emission in detail. Copyright (c) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.