Kotter is a graduate of MIT and Harvard. He joined the Harvard Business School faculty in 1972. In 1980, at the age of thirty-three, he was voted tenure and a full professorship

Why do we need leaders?

Leadership is required for mobilising people to handle challenging times. In a world that has no challenges, things are fine and you don't require leaders. In such a world you don't need to mobilise people for handling any crisis. But unfortunately in our world we have huge number of challenges in the government, non profit and business sectors; we have many challenges in the developing and the developed world. Hence we require leadership in our world. In fact in our world the need for leadership is more now than ever before. In our current business world, we cannot afford to restrict leadership just to the top management positions. Every employee, every engineer should rise in to a leadership role. They should step in to solve customer problems; they should step in to solve internal company problems.

The number of people that we need to provide leadership is huge now. The turbulences in life will never stabilise and I see the demand for leaders steadily going up.

How are leaders different from managers?

Leaders mobilise people. Their role is to undertake challenging goals that involve change. Leaders focus on changing behaviour, while managers focus on existing circumstances. For example if there is a DVD player that is built well, we don't require a leader to press the on/off button, because there is no challenge in it and no change is involved. I am not saying that managers are not important. Of course they are important since it is not just the story of one DVD player. It is the story of 100,000 DVD players in 20 different countries where things can get complicated. Managers are important that they should manage all these different DVD players in different countries and ensure that they play the right movies at the right time. But the role of leaders is different. They often create the systems which the managers manage. For example initially there was the VHS system and the tapes which we were used to. It took leadership to change the user habits in to something better. In the case of the battle between Sony and VHS the amount of leadership that was required initially to drive the battle was much greater than after they won. Leadership is important at times of change because most of the times the systems are not in place and leaders drive change and face the challenges which are humongous.

So in short, in the case of stable existing systems you need managers, while in the case of new turbulent situations that require a change you need leaders.