In 1977, Psychoanalyst and Harvard professor Abraham Zaleznick put forward a theory that management and leadership were very different things, and made the case that managers and leaders were very different people. Up to this time in organizational development, corporations were focused on process, efficiency, hierarchy, and control. Managers were expected to develop the skills and experience to manage people and resources, thereby increasing productivity and output.
Zaleznick said that leadership was also an essential factor in the success of a corporation. Leaders are able to motivate people through vision and innovation. Leaders have an almost mystical quality; they don't have employees as much as they have followers. He used Edwin Land and the invention of the Polaroid camera as an example of how vision comes before product. A more contemporary example would be Steve Jobs and Apple Computer.
The debate over this theory is not whether such a division is true, but whether both qualities can be found in one person. Zaleznick made the case that people who are drawn to process and structure are naturally inclined to be managers. They seek order out of chaos. In contrast, leaders have the ability to influence people through creative expression and abstract ideas. Zaleznick believed that while managers could be trained, the qualities that leaders possess are mostly an innate part of their personality. Combining one with the other was like pairing a boxer with a kangaroo.
Notably, Zaleznick felt that leaders had more in common with artists than with managers. Those of us that work in the performing arts certainly find evidence of this in the many cultural organizations that were founded by visionary choreographers, theatre directors, and musicians. But there is more to this parallel-- we often see that creative types can sometimes be difficult to work for (and with). And so we have this paradox; we need leadership to create the vision, but management to make it a reality. Zaleznick understood this need, but maintained that these were distinct talents held by different individuals.
As a Taoist of course I favor the dualism of one thing versus the separateness of two things. Leaders can be managers, and managers can lead. Yin cannot exist without yang, and yang cannot exist without yin. A leader is who you are; a manager is what you do. I believe most people have some capacity for both. It is a question of strengths and balance. As a leader, you have to recognize that employees need more than a vision to support the goal. They need structure and concrete action plans. As a manager if organization and process is your strength, you need to add in a dose of aspiration to motivate your team. If you know what is needed and you still recognize that one or the other quality is not your strength, you should take Zaleznick's approach and actively seek to find it in others.