XMM-Newton is the largest research satellite built in Europe ever. With about 300 refereed papers published each year, XMM-Newton is one of the most successful scientific missions of the European Space Agency. The talk gives an overview of the scientific highlights and achievements covering all astrophysical areas from charge exchange found in nearby comets up to the most distant clusters of galaxies. Many XMM-Newton observations address directly cosmological questions like dark matter. Several exciting scientific perspectives for the mission's future will be discussed as well.