|Title||Massive stars as tracers for stellar and galactochemical evolution|
Massive stars are key drivers of the cosmic cycle of matter. Because of their enormous luminosities they are ideal indicators for the study of stellar populations over large distances, throughout the Milky Way, other galaxies of the Local Group. and beyond. Recent advances in the modelling of the atmospheres of massive stars allow stellar parameters and elemental abundances to be constrained with unprecedented accuracy. The implications of these on the derivation of observational constraints on massive star evolution and on galactochemical evolution will be discussed, providing tight guidelines for refinements of the contemporary theoretical framework.