Genetic maps constitute a tool for the comparison of the genomes of kindred species where regions can be spotted in which the order of markers is preserved (synteny) and genes of interest can be located. They are in current use for the identification of genome zones involved in complex characters (QTL). The methods of drawing these maps are briefly described ; they are common to all species, but may be sometimes more complex in the forage species, due to the frequent allogamy and polyploidy of the latter. The maps presently available for forage species are described. In the grasses, maps have been obtained for the diploid ryegrasses, both the Perennial and the Italian. Maps of several fescue species are also available, for various levels of ploidy. Work is in progress for lawn species, but nothing has yet been published regarding the less frequently grown and polyploid forage grasses (in the genera Phleum, Dactylis, Bromus, etc.). For forage legumes, several maps have been published : for Lucerne (both diploid and tetraploid), White Clover, Red Clover, Birdsfoot-trefoil, and Vetchling (Lathyrus). Maps of the two model legumes, Medicago truncatula and Lotus japonicus have also been obtained. No work has yet been published on the economically minor legume species : Subterranean Trefoil, Sainfoin (Onobrychis), Crown Vetch. There is an important synteny among forage grass species, and also between them and other grasses such as wheat and rice. Similarly, there is a very large synteny among the legume species. These high levels of synteny make it possible to transfer the knowledge acquired on model species (such as rice and Medicago truncatula) to the forage species.