The creation of the World Wide Web has had a profound impact on the ease with which information can be distributed and presented. In the sequence, there has been an increasing interest from professionals, public and politicians to make publicly available the tremendous wealth of information kept in museums, archives and libraries, the so-called “memory organisations”. Quite naturally, their development has focussed on individual presentations – websites and interfaces to their local databases.

Now with more and more information becoming available, there is an increasing demand for targeted global search, comparative studies, data transfer and data migration between heterogeneous sources of cultural contents. This requires interoperability not only on the encoding level - a task solved well by XML for instance - but also of the complex semantics, which are characteristic for this domain.