The aim of this paper is to present a prospective vision of the transport area, showing the main potential effects of the motor vehicles on the environment. A comparison will be made between the legislations controlling the limits of emissions of polluting gases coming from motor vehicles, of several countries such as USA, Japan, Brazil, and Economic European Community.Some solutions to reduce the consumption of fuels and consequently the levels of emission of polluting gases will be mentioned. A short analysis of the alternative fuels that could be used, will also be made. The fuels to be analyzed are: hydrogen, electricity, natural gas, ethanol, methanol and solar energy. For each fuel, the main advantages and disadvantages will be discussed taking into account its use and the state of research reached in some car factories today.