Most of us probably think of people who play office politics as being opportunistic, manipulative, or devious and driven by the ambition to move up at work, writes Fortune’s Anne Fisher in her Nov. 29 column. But an expert she talked with says playing politics is an essential art that involves “building relationships that will help you and your team accomplish more than you could on your own.”

What do you think? Can office politics ever be positive? Or have you only seen the negative effects? What are the best and worst examples of office politics you’ve seen?