Epitaxial films of CdS were grown on CdS, ZnS, GaAs, Ge, mica, and SrF2substrates using a chemical transport reaction. Electron diffraction, ion blocking and scattering, microscopy, and etch studies of the CdS films were carried out. The surface morphology of the films was studied. A correlation between some structures on the surface of the films and the experimentally and theoretically derived equilibrium forms of CdS crystals was noted. It is concluded that the principal growth mechanism of the epitaxial CdS films is through surface nucleation.