Cem Kaner has proposed a Software Customer Bill of Rights . While the paper is oriented toward software as a product -- and addresses whether people should be able to sue vendors that ship defective software -- it touches on the ideas of brand promise  and customer service, as well.
When working with business partners, organizations have contracts to fall back on. But what contract do you offer your customers beyond a warranty, if that? If you developed a bill of rights for your customers and clients, what would it say?