I was wondering what sort of wording people on here use in reference to accessibility within website contracts/agreements, e.g. would you just put something fairly general like:

'The site will conform to W3C Web Content Accessibility Guidelines'

Or would you specify minimum conformance Level A, or Double-A, and would you mention something about WCAG 1.0 changing to WCAG 2.0 sometime soon and therefore taking account of that should the change happen during the site development?

I'm coming at this from the other side - I'm on a website working group at work and we have an external contractor doing a new site for us. They have currently put that the website will 'Conform to W3C accessibility standards', so what I'm really asking here is whether I should be asking them to spell it out a bit more specifically?