This paper presents the means Arianespace provides for launching small satellites into geostationary transfer orbit (GTO) or low Earth orbit (LEO) and reviews actual as well as potential applications for lightsats. Small satellites weighing less than 50 kg are microsatellites. Satellites with a mass of a few hundred kilograms not exceeding 1 ton are minisatellites. Microsatellites are typically built by universities, research laboratories or radio amateur organizations and do not constitute a commercial market. Minisatellites on the other hand may have all the functions and the operational life-span of large satellites and may be used for a wide variety of missions.