I've been doing a bit of research into the law that governs accessiblity in the UK. Here, we have the Disability Discrimination Act that protects disabled people against all forms of discrimination.
Until now, I thought that covered web and multimedia production too, but it seems not.
The Disability Rights Commission code of practice for Rights of Access to Goods, Facilities, Services and Premises, section 2.40, examines the responsibility of Manufacturers and Designers of Products as follows:
“The manufacture and design of products are not in themselves covered by Part III of the Act because they do not involve the provision of services direct to the public. Nothing in the Act requires manufacturers or designers to make changes to their products, packaging or instructions. However, it makes good business sense for manufacturers and designers to make their goods (and user information) more accessible to disabled customers and they should consider doing so as a matter of good practice.”
It appears that unless your project provides a service to the general public (basically government or education) then the DDA doesn't cover you.
I know there are other good reasons for making accessible websites, and I personally will try and continue to do so, but the big threat of legal action that designers could bash their clients around the head with doesn't actually hold up in reality.
NB. This is just my interpretation of the law. If someone can advise me otherwise, let's hear it.
edit: here's the link if you fancy a butchers...