The W3C released a set of Notes on Web Content Accessibility, including an overview and Notes describing HTML guidelines, CSS guidelines, and Core techniques, some of which may apply to XML.

While accessibility hasn't been an issue raised frequently with XML itself, these Notes inform practices which will apply to the use of XML as a format containing information meant to be presented to humans. These notes also take advantages of practices, notably validation, which the W3C has been pushing for a while but which are receiving additional momentum because of the rise of XML and XHTML.

The Core techniques document begins with a discussion of the separation between structure and presentation, urging developers to structure their data separately from the rules intended for its presentation.

In a comment which suggests the coming integration of SVG, MathML, and other markup languages beyond HTML, it asks developers that "When an appropriate markup language exists, use markup rather than images to convey information" and notes that "The separation of presentation from structure in XML documents is inherent. "

Perhaps because it is unfinished, XSL receives little coverage in these documents, though some of the guidelines for CSS might apply. The Core Techniques document does suggest that developers "Use W3C technologies when they are available and appropriate for a task and use the latest versions when supported," and notes XSL and XSLT among those technologies.