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. One of the main topics of XMM-Newton observations are black holes. These observations address questions from the innermost environment around black holes, where the mass and spin of black holes can be traced, up to the impact of the black hole feedback on the structure formation in the universe over cosmological times. The talk gives an overview of the scientific highlights and achievements of XMM-Newton back hole research and discusses scientific perspectives for future observations.