Hydrolysis and condensation of tetramethyl orthosilicate (TMOS) in alcohol solutions of hydrated metal salts have been studied. The alcohols were methanol and ethanol, and the metal salts were nickel nitrate hexahydrate (Ni(NO 3 ) 2 .6H 2 O) and calcium nitrate tetrahydrate (Ca(NO 3 ) 2 .4H 2 O). The reactions were followed by means of FT-IR spectroscopy and the rate constants were calculated by using multiple linear regression. The results show that both the hydrolysis and the condensation rates increase with increasing amounts of hydration water. There is also a pronounced difference in the reactions when different metal salts are used. The nickel systems have a much faster hydrolysis rate than the calcium systems. This is probably due to different dissociation states in the two metal complexes. In addition some influence of the solvent was found.