The understanding of the subduction-related processes benefited by the studies of the high-pressure (HP) metamorphic rocks from the western Alps. The most stimulating information was obtained from the inner part of

the western Alpine belt, where most tectonic units show an early Alpine eclogite-facies recrystallisation. This is especially true for the Austroalpine Sesia Zone and the Penninic Dora-Maira massif. From the Sesia zone,

which consists of a wide spectrum of continental crust lithologies recrystallised to quartz-eclogite-facies mineral assemblages, the first finding of a jadeite-bearing meta-granitoid has been described, supporting evidence that even continental crust may subduct into the mantle.

From the Dora-Maira massif the first occurrence of regional metamorphic coesite has been reported, opening the new fertile field of the ultrahigh-pressure metamorphism (UHPM), which is now becoming the rule in the collisional orogenic belts.