Making AJAX Accessible
"Ask yourself “Do I really need AJAX?”. If yes use progressive enhancement. This means build a standard application then overlay with AJAX i.e. HIJAX.
The RNIB UK wrote a good article about it that says: "Early in Spetember I presented at the Irish Design for All e-Accessibility Network on accessibility and AJAX. It was a great opportunity to meet people and discuss issues as well as a chance to listen to presentations given by Steve Faulkner from The Paciello Group, Joshua O’Conner from National Council for the Blind of Ireland and Des Traynor
