Whilst it is a common task in systems integration to have to transform between di erent semantic data models, such inter-model transformations are often speci ed in an ad hoc manner. Further, they are usually based on transforming all data into one common data model, which may not contain suitable data constructs to model directly all aspects of the data models being integrated. Our approach is to de ne each of these data models in terms of a lower-level hypergraph-based data model. We show how such de nitions can be used to automatically derive schema transformation operators for the higher-level data models. We also show how these higher-level transformations can be used to perform inter-model transformations, and to de ne inter-model links.