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3. The Government Digital Service has published copious content about accessibility. A good place Good places to start is are the Accessibility Campaign landing page and Understanding accessibility requirements for public sector bodies.
4. WebAIM is a not-for-profit organisation dedicated to furthering knowledge, technical skills and tools to improve web accessibility. One of these is its WAVE or Web Accessibility Evaluation tool. Paste any URL into the field at the top to get an automatic assessment of a web page's accessibility. (NB automated accessibility testers like this are generally thought to pick up only 20-30% of accessibility issues on a web page – the rest must be done by human checking.)
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