Preceramic polymers and expansion agents are being investigated to produce composite ceramic coatings for oxidation protection of metallic substrates. In this paper, we present results of a systematic approach to selecting the preceramic polymer and expansion agents and the optimization of the processing parameters to produce composite ceramics. Six commercially available poly(silsesquioxane) polymers and a polysiloxane were studied. In addition, several metals and an intermetallic were considered as potential expansion agents. Based on this study, the most desirable polymer/expansion agent combination and optimal processing parameters have been identified.