Topic Maps hold out great promise as a way to simplify data integration and presenting an easy-to-use interface to integrated data sets. Through merging, it is easy to build an integrated data set; the challenge is keeping the merged data set up to date.

This paper provides a procedure by which a subset of one topic map can be automatically synchronized by a subset of another topic map, in such a way that all updates to the source topic map will make their way into the target topic map. The procedure is flexible, and can meet a large variety of use cases. This effectively solves the update problem in a generalized way.