This chapter provides a brief overview of recent progress in the synthesis of silica-coated nanomaterials and their significant impact in different areas such as spectroscopy, magnetism, catalysis, and biology. The need to increase the topological complexity of colloid-based structures for the creation of designer materials with specific functionalities demands a better understanding of the relationships between material topology and material function. A number of reports have been devoted to silica coating of colloidal nanoparticles by aqueous classical methods such as Stober synthesis, use of silane coupling agents, and the sodium silicate water-glass methodology. Microemulsions are macroscopically homogeneous mixtures of water, organic solvent (oil), and surfactant, which on the microscopic level consist of heterogeneous domains of water and organic solvent separated by a surfactant monolayer. Various general approaches toward silica coating of inorganic nanoparticles within W/O microemulsions have been considered so far.