Forms and errors

Hello,

I have been looking for forms that are smart when it comes to displaying error messages. I looked at a dozen websites of the CSS/HTML lead thinkers (I’m talking about people who speak, write books). I’ve been incredibly disappointed. Their forms suck.

Could someone point me to an exemple of a form that clearly highlights the problematic fields, is smart when it comes to diplaying its messages, and is accessible.

Best.

rh