The Website Accessibility Initiative (WAI) outlines the international guidelines on accessible web design.

The WAI is affiliated with the World Wide Web Consortium (W3C) and works with organisations around the world to increase the accessibility of the web through five primary areas of work: technology, guidelines, tools, education and outreach, and research and development.

As part of this work the WAI published the first version of the Web Content Accessibility Guidelines (WCAG) in 1999. These are accepted as the definitive set of international guidelines used for building accessible websites. All other guidelines and standards are derived from these.

UK Government recommendations:

‘The page must comply with the WAI ‘A’ standard’

Guidelines for UK Government websites
Illustrated handbook for Web management teams

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