The chemical interactions between several aluminosilicate glasses and components at the anode side of SOFC have been investigated. Severe reactions occur if the modifier ions are Ba and Ca. MgO base sealants have been investigated in detail. The formation of some detrimental phases are seen. Cordierite forms with many reaction mixtures of sealants with ZrO2 stabilized with 8 mol % Y2O3 (as electrolyte) or nickel (as anode). On the other hand, with oxide dispersion strengthened Cr5Fe1Y(2)O(3) and steel, another detrimental phase, cristobalite, is favored. There appears to be a competitive formation of these two detrimental phases in some cases. In some of the interactions none of the detrimental phases appears. The diffusion behavior of the cations across the interfaces has been investigated. Among all the cations, chromium diffuses the maximum. The diffusion coefficient of chromium for the diffusion couples of different sealants with ODS alloy have been determined.