Is the person your peer, your boss, whatever. If the person is your boss, just say, "Boss, you did X." The boss says, "I want you to do Y." Say, "OK, here's why I did X." You present your case, you try to sell. Your boss says, "I still want you to do Y. Let's talk about how to make Y work."
If it's your peer, then you have to figure out, well, is this the battle I want to fight with my peer? Is it important, is it meaningful or not? If it's a big deal, you know what? Then fight the battle. If it's not a big deal, take a deep breath and let it go.
Whatever happens, though, you go to that meeting...peace. And you try to walk out of that meeting just to achieve results. You don't turn the meeting into a contest about who's smarter or better than the other person.
Last updated January 24 2008: 1:37 PM ET