A New Approach for XML

Actually, Two Approaches

Building on SGML/HyTime XLink uses ideas from the much more sophisticated (and much more complicated) SGML HyTime standard for hypertext linking, stripping them down to a much simpler set of tools.
Architectural Forms for Integration One of the key tools from HyTime, architectural forms, provided the original backbone of XLink.
Namespaces for Unique Identifiers More recent drafts of XLink use XML namespaces to keep the XLink vocabulary out of the way of other element names. XLink's set of global attributes can be used with any DTD or schema, and don't have a DTD or schema of their own.