and the aggregation of a greater variety of multi-media documents. Advances in technology and reductions in cost and size have produced many 'desk-top' publishing systems in the market place. More sophisticated systems are targeted at the high end of the market for newspaper production and quality color output. Outstanding issues in desk-top publishing systems include interactive editing of structured documents, integration of text and graphics, page description languages, standards, and the human- computer interface to documentation systems. The latter area is becoming increasingly important: usability by non-specialists and flexibility across application areas are two current concerns. One of the objectives of current work is to bring the production of high quality documents within the capability of naive users as well as experts.