This book covers experimental results of Brillouin and Raman light scattering as well as NMR spectroscopy measurements elucidating structural, vibrational, elastic, photoelastic and magnetic properties of europia doped soda magnesia aluminosilicate glasses as a function of the content of individual glass components to provide new knowledge related to the mechanism underlying the formation of holographic gratings in these materials. The effect of rare earth oxide doping, alumina and soda substitution for silica are discussed in terms of changes in measured hardness, compressibility,...