A friend of mine—one of the most effective leaders I know—has produced remarkable results that span several decades at two very large organizations, and is now taking on a third one. He's the kind of guy that you naturally want to be with.

He shared with me one of the keys to his success. When he takes the reins of leadership somewhere, the first thing he will do is get rid of the people who are negative. "I can't afford the energy that will get siphoned off by whiners and victims and blamers and drainers," he told me. So the first step he takes in building a team is creating a family of positive, visionary, excited, and basically happy people.

Another friend of mine, who has worked both inside and outside the church, says that this is easier to do when you work at a corporation than it is when you work at a church.

But it did spark my thinking: what makes some people energy-bringers and others energy-drainers?

Obstacles or opportunities?

Carol Dweck is a world-renowned Stanford ...