Summary of the main leadership theories
| Era | Period | Theory | Description |
| Trait | 1840s 1930s–1940s | Great Man Trait | Focus on natural born leaders Focus on identifying traits and characteristics of effective leaders |
| Behavioural | 1940s–1950s | Behavioural | Focus on the actions and skills of leaders |
| Situational | 1960s | Contingent and Situational | Focus on leaders adapting their style taking into account the environment |
| New leadership | 1990s 1990s 2000s 2000s 2000s | Transactional Transformational Shared Collaborative Collective Servant Inclusive Complexity | Focus on leadership as a cost–benefit exchange Focus on an inspirational style pushing followers to higher and higher levels of achievement Focus on followers leading each other Focus on engaging followers. Person-centred style Focus on the whole system of an organisation |