Inorganic silica nanoparticles were encapsulated with an epoxy resin to give waterborne nanocomposite dispersions, using the phase-inversion emulsification technique. Sub-micron-sized waterborne particles with narrow size distribution were prepared such. Microscopy results indicate that all the silica nanoparticles are encapsulated within the composites and uniformly dispersed therein. Curing of the nanocomposite dispersions proceeded in a controlled manner.