Bill George is the author of two books, True North and Authentic Leadership. He is the former CEO of Medtronic  (NYSE: MDT). During his 10-year tenure, he instilled values, inspired employees, delighted customers, and led the company to a 60-fold increase in its value -- equivalent to 35% investment returns per year. Motley Fool CEO Tom Gardner interviewed Bill several months ago to get his thoughts on what makes for great leaders. This is part four of six in our interview series. Please click here to read Part 1, and to find links to the rest of the series.

Tom Gardner: I want to hear a bit about your thinking on how to manage your own life as a leader. I have to admit that as an investor, I have met some CEOs who actually delivered great results and a great-performing stock for me as an investor, and some of those CEOs have been people who lead pretty imbalanced lives. You talk and write about the importance of family and friendships outside work. How do you factor into your evaluation of the obsession, passion, enthusiasm and everyday extreme commitment of a great leader with their desire to have a sustainable model for living and leading?

Bill George: Yeah, the key word you used there is "sustainable." And I think that goes right to investors. I used to talk to investors at Medtronic and say, "What are you looking for? Are you looking for great results this year? Are you looking for sustainably great results over 10 years? Because that is what we are going to perform to. We are not going to have earnings up 50% one year and down 30% the next. We are going to achieve 20% growth every year. If that is what you want, then this is the place to come, but that requires a different kind of leadership, sustainable leadership. And the qualities of that are very different."

Many of my students at Harvard get caught up in working 100-hour weeks. You simply can't sustain that kind of work pace or that kind of work life. You will burn out. And if you have an organization that is filled with a lot of burnout, it will eventually collapse. It will collapse of its own weight. You will not have the infrastructure; you will not have the essence of the organization strong enough to carry it through difficult times.

So I think all of us work hard. I'm not suggesting anything short of working hard. But I think you need to get some perspective if you are at work 100 hours a week. If you are flying all around the world all the time and never get time with your family and your community, you won't make good decisions. When you're burning out, it all becomes about you and about decisions you make, rather than how you empower other people to make great decisions. So let's just say success in business requires hard work, but if there is not some kind of balance with one's personal life, community life, family life, you are not going to get sustainable, good results from those leaders.

Gardner: Bill, it has to be said that your tenure at Medtronic marks one of the greatest 10-year performances at any public company in American history. How did you manage stress, personally, during that period?

George: Well, there was lots of stress, I can tell you. Every day you had a potential problem with a lawsuit or a product going to be recalled by the FDA, or a competitor like Boston Scientific (NYSE:BSX) or Johnson & Johnson (NYSE:JNJ) coming out with a competitive new product. And you had pressure to make the earnings every quarter. I think we made our earnings 47 out of 48 quarters I was there, so that is stressful. Anyone who says there is no stress … it is nonsense.

So, you are right to ask, "How do you manage stress?" I think, again, it gets back to balance. I meditate 20 minutes twice a day, and that helps me relieve the stress. I used to coach soccer, even when I was CEO of Medtronic -- youth soccer. Of course, I always had to have a co-coach because of my travel schedule. I had a wife who was, in addition to being a great wife, also a great advisor, and she would help counsel me on difficult decisions or times when I was feeling down or help me put things in perspective about what was important and what wasn't important. I found that just invaluable.

I believe very strongly, Tom, you have got to have a support team around you to be successful as a leader. I have a men's group I have been meeting with for over 30 years. I have a couple's group that has been meeting for 25 years. Groups like this help give you perspective because they know your strengths, they know your weaknesses. Again, they can pick you up when you are down; they can point out to you that you are getting a little high on yourself when you think things are going well. Having that support team, having a great mentor, someone you can call and say, "Hey, give me your help. I don't know what to do here." All of these are invaluable elements of how you can be successful.

They also reduce the pressure. Listen: Stress itself isn't bad, but the loneliness that can come with it can cause you to make bad decisions. Having a support team keeps you from making bad decisions.

Gardner: Out of curiosity, what is your success rate at predicting whether someone is an authentic leader? How long does it take for you to make a determination, and how often do you think you are right?

George: I think you can tell pretty quickly. Certainly in my students, as I learn their stories, it all gets reinforced. You hear about their life stores or crucibles. If I know them personally, it's easy. If I am just reading about them in the media, it is easier to get fooled. If you know them personally, I would say you can learn within a matter of hours of knowing someone, of being with them, seeing them up close and personal.

Success rate? Oh, I would say 80%, 90%. I think people who are not authentic give off a lot of signals. And sometimes you will see people with really high performance at companies that just aren't treating others well. Some of the boards on which I have served, when people are identified as high performers, I sometimes say, "Watch out for this person. I don't really trust that person." Sometimes, top management is really impressed with them. I say, "You know, I am not comfortable with this person. They are just too slick for me. I think they tell me what I want to hear; they don't tell me what I need to."

I quiz people a lot when I am in meetings, whether as the CEO or now as a board member of some major corporations. I quiz people fairly intensely to find out what they are made of, and will they shoot straight with me? Will they admit when they are wrong? Anyone who can't admit they are wrong to me can't be very authentic.

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