The formation of solid solutions of the type [Ba(HOC2H4OH)(4)][Sn1-xGex(OC2H4O)(3)] as BaSn1-x/GexO3 precursor and the phase evolution during its thermal decomposition are described in this paper. The 1,2-ethanediolato complexes can be decomposed to nano-sized BaSn1-x/GexO3 preceramic powders. Samples with x = 0.05 consist of only a Ba(Sn,Ge)O-3 phase, whereas powders with x = 0.15 and 0.25 show diffraction patterns of both the Ba(Sn,Ge)O-3 and BaGeO3 phase. The sintering behaviour was investigated on powders with a BaGeO3 content of 5 and 15 mol%. These powders show a specific surface area of 15.4-15.9 m(2)/g and were obtained from calcination above 800 degrees C. The addition of BaGeO3 reduced the sintering temperature of the ceramics drastically. BaSn0.95Ge0.05O3 ceramics with a relative density of at least 90% can be obtained by sintering at 1150 degrees C for 1 h. The ceramic bodies reveal a fine microstructure with cubical-shaped grains between 0.25 and 0.6 mu m. For dense ceramics, the sintering temperature could be reduced down to 1090 degrees C, when the soaking time was extended up to 10 h.