Joseph Rost in his much discussed ‘Leadership for the 21st century’  complained that despite the abundance of literature on leadership there was still no definitive definition available, none that encompassed the key elements that are perceived as crucial to a contemporary definition: so according to Rost  "Leadership is great men and Women with certain preferred traits influencing followers to do what the leaders wish, in order to achieve group or organisational goals, that reflect excellence defined as some higher order effectiveness”. This definition seems to give credence to the long established, idealised and cherished vision of the ‘hero-leader’ as described by Senge who argues that because of this persistent myth of the ‘omnipotent CEO’, all too often we still see leaders as “…the few special people blessed with the capability for command and influence”.
It is notable that House  noticed that the definition of leadership was progressively broadening to include the idea of “contributing to social order, introducing major change, giving meaning and purpose to work and to organisations, empowering followers and infusing organisations with values and ideology”.
Ultimately there is logic in what Ciulla  asserts:- that leadership is not radically different for different theorists, and there is a resemblance in all of the definitions, so that everyone would understand what the other meant if placed in a room together, and she concludes that the real difference is in the “…implications for the leader/follower relationship and how leaders get people to do things…and how what is to be done is decided”.
Although historically we can trace the study of leaders back centuries, essentially in more recent history we had the ‘great man’ followed closely by ‘Trait theory’ which identified certain qualities that were to be found in great leaders, which were a combination of physical characteristics as well as skills and talents. Early theorists like Galton surmised that leaders were born, not made. Subsequently, the ‘behavioural’ and ‘situational’ models appeared which were based on the more transactional ‘do as I say’ style and whose prime focus was to maintain order.
Subsequently numerous other theories of leadership have developed that fall under the heading of ‘positive leadership’ whose main aim was to move away from ‘situational’ or ‘Transactional’ leadership styles. The 1980’s witnessed the birth of the ‘new paradigm’ leadership models of ‘Transformational leadership’ which encompassed charismatic and inspirational leadership styles. This model of leadership gave rise to an abundance of literature analysing and dissecting what it means to be a ‘transformational leader’. Unfortunately despite all of this work , the issue of diversity was largely ignored and the ‘heroic’ leadership model ascended and took root through the 80’s and 90’s
Almost anyone can attend a ‘leadership development’ program ( of which there are too many to choose from) that purports to turn you into a leader in record time, however in my experience and in my development as a leader, competancies and ‘tick box’ exercises do not make a leader, we need to go deeper.
Why leadership is relevant now
The cult of the leader and what it means has never been more ripe for discussion, because we are no longer focused solely on the needs of western societies. we now have the impact of globalisation, with the broader cultural context of leadership up for consideration.
Contemporary critiques of leadership point towards the need for a new model of leadership. Theorists like Rost  and Avolio  had been voicing the need for a new leadership paradigm for the 21st century for several years before the recent global events that have resulted in an almost audible global clamour for a new leadership paradigm: closer to home the swiftly changing operating landscape that businesses are in, requires leaders to be able to navigate their teams through change quickly and sustainably.