What have you found to be the most effective ways to communicate and negotiate with kids?

I think most kids should be CEOs – they are such good negotiators! I do not have the answer to this one. I would like to say sit down and explain things to them, but many times when they challenge me about a decision I respond with “because I’m the mother”! I do not have the time always to enter into long- winded explanations. Having said that, I am always very honest and reasonable, so if they can present a good argument, I am willing to go with it.