The Laboratory of Spectroscopy of Functional Materials (acronym LEMAF in Portuguese) at the São Carlos Physics Institute (IFSC) of the University of São Paulo (USP) is dedicated to the research of functional materials, with special interest on luminescent materials. Our research is based on the planning, synthesis and characterization (both structural and photophysical) of glass, glass-ceramics and nanocomposite materials. These materials are of special interest for a number of technological devices such as laser active media, amplifiers, sensors, electroluminescent cells, etc. LEMAF’s distinguishing trait is its capability of establishing correlations between photophysical properties and the materials structure organization and then using these correlations as feedback for the new compositions and synthesis processes in order to optimize the desired properties of the materials. For this purpose, we apply and develop modern NMR, EPR and UV-VIS spectroscopy techniques in association with theoretical studies for a better understanding of the fundamental processes occurring in these functional materials.