Ovidius TreeVision is a graphical SGML and XML DTD visualization and analysis tool for end users and DTD developers.
Main features are: Load/Reload SGML/XML DTDs, visualize DTD as a dynamic tree, navigate in DTDs, search for elements, their contexts and attributes, generate graphics (with image maps) for DTDs, subtrees and individual elements.
Requires Java Runtime Environment 5.0
30 day fully functional demo version is available for download