The application of magnetically doped semiconductors in opto-electronic and spin-electronic devices as well as in quantum computing will have a tremendous scientific and technological importance for the future years. The aim of our project is thus to understand and to predict new materials and novel phenomena for nanomagnetism and spinelectronics. Our approach relies on calculations of the electronic and magnetic structure based on the density functional formalism, which is well suited for a realistic description of the materials and properties involved. Our calculations of the magnetic properties will allow to identify the relevant exchange mechanisms (Zener p-d- exchange, double exchange, super exchange) and the interaction between magnetic moment formation and the electronic structure of the host lattice. Our study also includes the determination of the type of magnetic order, FM, AFM etc. and possible non-collinear magnetic states. Magnetic ordering temperatures, which are of central importance for the application, will mostly be determined from calculations of the exchange parameters. Our investigation will cover p- and transition-element doped II/VI semiconductors like CdS, and ZnO, III/V- systems like GaN and InSb as well as doped graphene. The second important part of our research will investigate magnetism in doped perovskites. Starting from systems like SrTiO3 and BaTiO3 we will study hole doping by replacing oxygen by p-elements from the left site of the main group elements (N,C,P,Si,Al etc.), which will form magnetic moments interacting via the introduced holes. Also for these systems we will study the exchange mechanism. The introduction of magnetic moments in ferroelectric materials could provide a new route towards materials with a strong coupling between magnetic and electric polarization (multiferroics).