Context modeling using a UML profile facilitates interoperability of Web service definitions. While modeldriven methodologies are a generally accepted practice for generating Web service artifacts such as XSDs and WSDLs, they do not guarantee that the artifacts will be interoperable. To avoid interoperability issues, transformations from logical to physical models must be accomplished with an awareness of implementation context. An example case study based on our experience in using the IEC CIM model demonstrates the concept.