The cylinder head gasket of the past was built up on the basis of ashestos, which exhibits extraordinary properties for this special application. On the market, two basically different materials have substituted asbestos: expanded graphite and a filler-fibre matrix material. These two materials are compared with each other as well as with asbestos in regard to the properties essential to a cylinder head gasket material. The experimental tests are correlated with the results of engine tests. The specific advantages of the two non-asbestos materials are discussed in terms of those laboratory and engine tests.