Nanostructured glass-ceramics obtained by the adequate heat treatment of a Nd3+-doped glass with composition SiO2-Al2O3-Na2O-LaF3 have been investigated by several techniques. X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) show that the precipitated nanocrystals are LaF3 with a crystal size between 9 and 13 nm. Furthermore, energy dispersive X-ray (EDX) analysis shows the incorporation of Nd3+ ions into the LaF3 nano-crystals. A detailed optical characterization clearly shows that Nd3+ ions in glass-ceramics are incorporated in both crystalline and amorphous phases. Steady-state and time-resolved site-selective laser spectroscopies allow to isolate unambiguously the emission of Nd3+ ions in LaF3 nanocrystals which shows extremely well defined spectra, similar to those obtained for pure LaF3 crystal.