Water-in-oil (W/O) microemulsion is a well-suitable confined reacting medium for the synthesis of structured functional nanoparticles of controlled size and shape. During the last decade. it allowed the synthesis of multi-functional silica nanoparticles with morphologies as various as core-shell, homogenous dispersion OF both together. The morphology and properties of the different intermediates and final materials obtained through this route are discussed in the light of UV-Vis-NIR spectroscopy, dynamic light scattering (DLS) and X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and magnetometer SQUID analysis. (C) 2009 Elsevier Inc. All rights reserved.