Automotive LPG is the most highly developed and widely used alternative fuel in the world. LPG having been included in the European Auto Oil 2 Program as part of the setting out of the fuel market of the future, and the fact that it aids in meeting the European Union air quality-related objectives at the lowest possible cost, means LPG’s having clearly been recognized as a clean fuel, signifying a boost to its future development. This study describes, first of all, the technical aspects of the use of LPG in both light and heavy duty vehicles. Of outstanding importance are the first-generation carburation systems, which were subsequently further improved by means of electronic control systems, in addition to what are known as third-generation gas-injection systems. In following, the advantages entailed in using LPG are discussed, focusing on its storage, the increase of the engine life and the lowering of regulated and non-regulated exhaust emissions. A description is also provided of the LPG’s performances, that is, power and fuel consumption. Much of what is said is based on the findings of different in-house tests conducted by Repsol-YPF. Lastly, the main needs are set out as regards of an LPG’s future development.