1. A method for invoking a web service between a service requestor and web service provider, the method comprising: receiving a web service request from a service requestor, wherein the receiving is by an intermediary, and wherein the request identifies a source tModel defining a service interface for communication between the intermediary and the service requestor and includes information defining a requested web service; retrieving, by the intermediary, an access client code structure for methods executable at a runtime to invoke web services; retrieving, by the intermediary, a mapping aspect corresponding to a service provider for the requested web service and having code for adapting the methods of the code structure to a target tModel defined aspect of a service interface supported by the service provider for the requested web service; and invoking the requested web service by the intermediary weaving the mapping aspect and the access client code structure at the runtime and executing the methods of the code structure as adapted by the mapping aspect, so that the invoking includes communication between the intermediary and the service provider according to the target tModel.