This work presents results of studies of the structural features of nanocrystalline doped Ce1−xMexO2−y samples (Me = Sm, Bi, Gd; X = 0–0.5) prepared via the polymerised precursor (Pechini) route by using a combination of diffraction (XRD, TEM, WAXS on SR) and spectroscopic (EXAFS, Raman, FTIRS of lattice modes, XPS, SIMS) methods.