There are cases when feeling angry can lead to better outcomes. Research by Gerben van Kleef at the University of Amsterdam demonstrates that in a onetime, transactional negotiation with few opportunities to collaborate to create value, an angry negotiator can wind up with a better deal. There may even be situations in which a negotiator decides to feign anger, because the counterpart, in an attempt to defuse that anger, is likely to give ground on terms. This might work well if you are haggling with a stranger to buy a car, for example.