Metal-rich stars accumulate their metals from previous generations of stars, and so contain the history of their galaxy. By studying these stars we can gain valuable insights into how metals change the formation and evolution of stars, and explain the extraordinary massive star populations observed in the metal-rich region of our own galaxy. Observations of metal-rich regions have shown that stars hosting giant planets are generally metal-rich, which has triggered further observations of metal-rich stars. This has led to the discovery of new exoplanets, and advances in the study of planet...

Massive stars play a crucial role in the Universe: they are important drivers for the photometric and chemical evolution of galaxies; they are sources of important elements, including those necessary for life; and, with their strong winds and supernova explosions, they feed the interstellar medium with momentum and kinetic energy, impacting on the star formation rate. Knowledge of the evolution of massive stars is important not only for stellar physics, but also for probing the evolution of galaxies and their star formation histories throughout cosmic time. This volume provides an...