Web Accessibility is primarily benefiting people with disabilities and changing abilities due to aging. If you are looking to commission a website please read PAS 78. I achieve accessibility by following Web Content Accessibility Guidelines 1.0 and WCAG Samurai aimed at web content developers like us by the World Wide Web Consortium (W3C). I am also an member of GAWDS an association of accessible web designers and developers. If you are a developer read one of my articles Building better websites by understanding blind users browsing behaviour.