Sometime around 1894, Harry Selfridge, then an executive at Marshall Field in Chicago, wrote and published for employees something called The Marshall Field & Company Idea. It put into writing how management expected their employees to conduct themselves in relation to their customers.
I would encourage every one of you who is a manager or supervisor of any kind of establishment anywhere in the world to print this and post it prominently on your door or cubicle, and to email it to every single person who works with you:
The idea is "To do the right thing, at the right time, in the right way; to do some things better than they were ever done before; to eliminate errors; to know both sides of the question; to be courteous; to be an example; to work for love of the work; to anticipate requirements; to develop resources; to recognize no impediments; to master circumstances; to act from reason rather than rule; to be satisfied with nothing short of perfection."
You can download an image of this quote here.