Using models in different contexts poses major integration challenges, ranging from technical to conceptual levels. Independently of each other developed model components cannot be expected to coincide in all description details, based on the same abstractions and assumptions. Variations in interface descriptions of model components have to be resolved. XML-based description languages from the area of web services provide standardized means for bridging diversities of implementations. This paper presents an adaption of the Web Services Description Language (WSDL) combined with XML Schema Definitions (XSD) to the specific requirements of model components in the area of discrete-event simulation. XML-based interface descriptions are integrated into a general model component architecture. Schema matching approaches provide the basis for syntactical compatibility checking of interfaces at the time of composition.