In recent years, Irish society has witnessed a significant decline in the pervasiveness of "authoritarian" styles of leadership. Whether it be in the classroom, the family, the church or the political arena, many of the old diehards have, if not died, certainly declined in influence. In the world of work we have also experienced dramatic changes in leadership styles.

Whilst the European Union enforces revisions via, for example, legislation on worker participation, the Japanese approach is reflected in teamwork and "total quality management", with "employee empowerment" to the fore. The American influence has long lauded a host of practices such as job satisfaction, together with routes like performance-related pay, direct communication and "open door" policies designed to emphasise the relationship between the manager and each member of staff.

Many of these developments reflect altered views of leadership. According to Alan Hooper at the Centre for Leadership Studies at Exeter University, the old authoritarian "command-and-control" management model is being transformed into something more empowering, that "seeks to unlock the potential in followers, rather than control their behaviours". Likewise "total quality" guru W. Edwards Deming insisted that if the workplace is to survive competitive market forces, it must "replace supervision with leadership".

The importance of good leadership to successful enterprises is reflected in the host of employers (like Abbot Laboratories, DuPont and the Ford motor company) renowned for the sizeable investments made in the development of their staff's leadership skills. These changes throw up many questions for the modern manager, such as: what is leadership? and, how can a leader be effective?

Penny Hughes, Coca-Cola's first female president, believes that "leadership is largely about an environment in which people can flourish". That is, "managing people is the prime responsibility of the leader". Whatever its roots, leadership can be described as a process whereby one exerts influence on others in an organisational context. Where such leadership is effective, it is the result of a meaningful relationship between the leader and those being led. As Hughes noted, effective management is a key feature of effective leadership.

Regrettably, the experts don't always agree as to what exactly constitutes good leadership. Furthermore some insist that "leaders are born, not made". That is, because of their innate personality traits, they're just cut out to be leaders. Others counter that "leaders are made, not born" - thus emphasising the importance of leadership qualities acquired through life's experiences. As Nelson Mandela put it: "experience is the foundation of leadership".

Whatever about the source of leadership skills, the question remains as to which style of leadership is best. Basically we can identify five styles:

Authoritarian: This is reflected in the leader who is rigid-thinking, highly critical, aggressive and domineering. For example, it may be reflected in the former British Prime Minister, Baroness Thatcher's style, as she warned: "I don't mind how much my Ministers talk - as long as they do what I say." As a management leadership style it is often evident - and occasionally essential - to the operations of An Garda S∅ochβna and the Defence Forces.

Transactional: This style appeals to the self-interest of staff via the provision of rewards for services. The widescale introduction of performance-related pay systems in Ireland in recent years clearly confirms the pertinence of this style.

In fact, it bears similarities to the old Theory X school of management, frequently brought to life via merit pay (i.e. "the carrot") and disciplinary measures (i.e. "the stick").

Transformational: This approach owes much to the inspirational or visionary leader, who transforms the aspirations of followers, inspiring them to perform better than expected. A powerful vision is a precondition for leading a company at any time. It is a persuasive picture - or corporate "mission statement" - of where you want to go, how you want to get there and why you should follow. One could see Martin Luther King, Mahatma Gandhi or even Richard Branson in this mode.

Self-Leadership: This style is about leading others to lead themselves. It supports lifestyle guru Stephen Covey's contention that leadership is "not about power but empowerment". Similarly, former American President Dwight Eisenhower - effectively supreme commander of the Allies during World War II - saw leadership in this vein. That is, as: "the art of getting someone else to do something you want done because he wants to do it".

Laissez-Faire: This style actually avoids decision-making and supervisory responsibility. The approach adopted by many of the protest groups to the G8 summits' globalisation policy closely resembles this almost anarchic style of leadership.

Modern management or leadership styles tend to be confined to the aforementioned "transactional" and "transformational" approaches. Whereas "transactional" leaders set objectives and use rewards and penalties to get staff onside, "transformational" leaders alert colleagues to their purpose and mission, whilst preferring to stir them to look beyond their own self-interest for the good of the group. This latter style is associated with leaders who display charisma, inspiration, intellectual stimulation and concern for the individual.

Such a persuasive model of leadership is especially attractive when it results in a highly motivated staff. Consequently, many management gurus extol its merit, with business success stories engineered by charismatic leaders and "coaching cultures".

Of course, successful leadership comes in all shapes and sizes, and what might be wonderfully effective in one situation could be disastrous in another. Consequently - like good managers - few leaders can be accused of rigidly applying one style. For example, Nelson Mandela prefers to combine the best ingredients of the transformational and self-leadership models when he compares the leader with a shepherd, staying behind the flock, letting the most nimble go ahead, as the others follow: "not realising that all along they are being directed from behind. Occasionally, though, the leader must also move out in a new direction, ahead of the flock, confident that he is leading his people the right way."

This "mix 'n' match" approach was also evident in much of Jack Charlton's reign as Ireland's soccer manager. Whilst the "authoritarian" style applied to all who surrounded him, a more considerate approach was reserved for star player Paul McGrath.

The British explorer Ernest Shackleton's journey to the Antarctic in 1914 provides us with a useful illustration of effective leadership in a crisis. His ship, carrying a team of 28, became trapped in ice and seemed doomed. However, his exceptional skills led to all being rescued after nearly two years.

The main leadership lessons taken from Shackleton's saga are: to engender optimism. As a way of maintaining morale, he openly planned the team's next expedition - to Alaska! Also, keep sight of the ultimate goal, but focus on interim objectives. Shackleton organised a trek across 314 miles of ice floe to an old food cache. It failed, but the collective endeavour restored the crew's spirits.

Next, minimise your prerequisites. Ten of the 28 were forced to use inadequate sleeping bags after the ship sank. Shackleton assigned these bags by lottery, save for the one that he took for himself.

Indeed Shackleton's preparedness to "rough it with the troops" tallies well with Superquinn Chief Executive Fergal Quinn's advice that: "the best way to lead is by example; people will follow more readily what you do than what you say".

One thing is for sure though; as the world's most popular book the Bible tells us: "If the blind lead the blind, both shall fall into the ditch." (Matthew 15:14.)

Dr Gerard McMahon is a lecturer in Human Resource Management at the Faculty of Business, Dublin Institute of Technology