Academics have yet to define what makes a great business leader; leaders come in lots of flavours.

From my management consultant perch I have come to prefer quiet, effective leaders. These leaders rarely appear in the media, are seldom quoted in national business newspapers, and do not write books glorifying their accomplishments. They are not showboats or public heroes.

Rather they choose to live behind the scenes and make the choices that drive a successful business. They are humble. It is not about them. Their ambition is the larger goal of leading the company to great heights.

The organization they lead has a well-articulated "noble purpose." It looks outwardly towards serving a customer. It is about customers, not profits. They start with the customer, for without a customer there is no business. When they look inwardly it is to improve the delivery of their customer value proposition.

They deliver consistent year-over-year results outperforming the market. Their companies typically achieve annually 5.5 per cent or more, adjusted for inflation, growth in revenues and earnings. They also earn their cost of capital.

Quiet leaders focus on the core business and grow the core. They may enter adjacent markets. Only occasionally do they grow through acquisition. They understand acquisitions generally fail to deliver expected outcomes.

These leaders obsess over change and how it might transform the customer. They ask: Who are our customers today? Who will they be tomorrow? What do our customers value?

For quiet, effective leaders, change is constant. They are transformational, relentlessly overhauling their companies. They inspire and motivate followers to achieve organizational rather than self-interest goals.

By contrast, transactional leaders are task-oriented, focussing on output such as increasing sales and reducing cost. Followers work for self-interest rewards dispensed by the transactional leader.

The quiet, effective leader has a strong resolve to deliver on the "noble purpose." They have a plan upon which they execute; like an outstanding golfer they play their own course with little concern for rivals.

The people trust their leadership. Their behaviour has earned them the trust of followers. The leader focuses on those doing the work; they delegate, aid followers, satisfy their needs, and create a supportive work environment. They focus on the individual, their personal advancement, growth and achievement.

Quiet leaders lead companies where the culture is positive. Little wonder the companies they lead rank as the best places to work.