Solid solutions of SiC and AIN have been prepared by the co-pyrolysis of polysilanes and organoaluminum amides. In the presence of ammonia. Si3N4 and AIN are formed. These materials are fully characterized by TEM, SAD, SEM, XRPD, and elemental analyses. The influence of reaction conditions, as well as precursor properties and reactivity, on the composition and morphology of these materials is addressed.