Directing, motivating, and enabling others to accomplish the mission professionally and ethically, while developing or improving capabilities that contribute to mission success. Effective leaders get the job done, look after their people, think and act in terms of the larger team, anticipate and adapt to change, and exemplify ethos in all they do.
- from Leadership in the Canadian Forces: Conceptual Foundations, National Defence and the Canadian Forces.
I've found no better definition of a leader anywhere else.
