Negotiators are always looking for ways to become better.  

We’ll read books, we’ll attend courses, and we’ll talk with the experts  in order to develop new negotiation styles and negotiating techniques.  Our ultimate goal is to find a way to make our next negotiation go  quicker and more smoothly as we work our way towards getting the deal  that will meet the needs of both sides. However, it turns out that one  of most powerful skills that we need to have in order to get what we  want from a negotiation may be right before us. 

Or, a better way to say  this, it may be on the sides of our head: our ears.