Contents:
1. Introduction
2. Theoretical Background
3. Computational Aspects
4. Green Functions
5. Formation, Interaction and Ordering of Local Magnetic Moments
6. Dynamical Mean Field Theory
7. Permanent Magnetic Materials
8. On the Icosahedral Metal-Phosphorus Coordination in Melliniite
9. Strong Correlation of Fe Impurities on a Cs Host
10. Magnetism of Supported Clusters
11. Magnetic Structure of Mn3Rh Alloys
12. Non-Newtonian Magnetization Dynamics, a Way to Accelerate the Switching of Local Units
13. Outlook and Future Perspectives
14. Svensk Sammanfattning
15. Resumo em Portugues
16. Acknowledgement