The chemical and mineralogical composition of rocks at convergent plate margins are a key to understand the interaction between the lithosphere of the lower and the upper plates as well as the mantle wedge. The geochemistry and isotopic patterns of subduction-related magmatic rocks reflect the conditions of magma genesis, ascent and emplacement that are related to the geodynamics of the entire subduction zone (e.g. subduction angle and convergence velocity, slab age, sediment subduction). Thermobarometry based on the mineral compositions of magmatic and metamorphic rocks reveals the PT-history of crustal units. These analytical results complement those of geochronology and tectonics to create a data base for geodynamic process simulations.