Metamorphosed mafic rocks in the Alps exhibit many characteristic mineral assemblages. They are used to study different phases of alpine metamorphism. The great variety of alpine metamorphosed mafic and ultramafic rocks is illustrated with a map of their distribution (plate I) and a listing showing their localities, size and thickness, metamorphic grade and tectonic situation. The localities: Prealpes romandes, Prealpes du Chablais, Versoyen, Haut Val de Suse, Montgenevre and Haute-Ubaye in the Western Alps and a N-S profile (Arosa-Oberhalbstein-Upper Engadine) in the Rhetic Alps are described in detail. The petrographie data could fit into a plate-tectonic model yielding different metamorphic events: a Jurassic to lower Cretaceous oceanic metamorphism, an upper Cretaceous to Eocene subduction metamorphism (low temperature and high pressure) and a postkinematic upper Eocene-Oligocene high temperature-metamorphism.