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The exhaust emissions from stoichiometric gas engines contain CO, Hydrocarbons and NOx besides CO2 and H2O. The Hydrocarbon emissions consist mostly of unburnt methane. Conventional Pt and Rh based three-way catalysts show a good performance for the conversion of CO and NOx at stoichiometric exhaust gas composition, but methane passes almost unconverted through the catalytic converter. At rich exhaust gas composition (Lambda = 0.995) higher conversion rates are achieved for methane, but the efficiency is still not satisfactory for instationary applications. Therefore specific catalyst formulations based on Pd were developed. Model gas reactor and first engine evaluation results are presented. The model gas data indicate that with Pd/Rh catalysts both a wider lambda window and a methane conversion of more than 90% can be achieved. Furthermore catalysts for lean burn applications were investigated.