I can only speak for myself, but I have no problem sharing with you that  during a negotiation I can become very, very frustrated with how things  are going. 

No matter if your negotiation styles and negotiating  techniques are causing things to go too slow, go off in the wrong  direction, or, even worse, not go anywhere. I start to become angrier and angrier as time passes. This, of course, leads to a fairly classic negotiating question. 

When you become angry during a negotiation, should you hide your emotions or should you show them to the other side?