Don’t go seeking conflict and confrontation, but don’t be afraid of it either. Both extremes are not good. Have a back bone and stand up for what you believe in, but do it tactfully and respectfully as to keep the negotiation going. If you shut a conversation or idea down, you’re treating it as a win-lose situation. That may be necessary for some things (hostage negotiations, for example), but if you want to have a long, meaningful relationship with that person there needs to be some “give and take.” If you always win (or lose), eventually that other person won’t want to deal with you anymore.