A brief review of polymer routes for the production of ceramics is given. The main emphasis is laid on systems derived from the single source precursor Cl3Si(NH)BCl2. This precursor has been developed in order to meet the objective of synthesizing amorphous multinary nitridic or carbidic ceramics. The synthesis of the single source precursor, its polymerization and finally pyrolysis to extended solids are reported. The amorphous materials obtained show outstanding properties with respect to thermal stability and resistivity against oxidation and crystallization.