I had an article published in the PMI Community Post last Friday on Servant Leadership. You can read it here. I've had a lot of feedback on the article and wanted to expand on what I said in the article.
Is Servant Leadership the only leadership style that a project manager should follow? The answer is no. Just like any other tool, this leadership style has its place. However, this style of leadership is part of the bigger picture. To be effective as a servant leader requires honesty, openness, willingness to listen, and compassion. Skills required of a servant leader, but of a good leader in general.
A project manager will be called on to perform other tasks that don't fit into the servant-leader model. For example, there may be a conflict on the team that the project manager has to step in to resolve. There's more management specific tasks like assigning resources or managing the budget.
So the project manager has to recognize when they should put on the servant leader hat. Following an agile project management approach leaves plenty of opportunities for acting as servant. The team is self-organizing, so they decide how to complete the work. The product owner is the one that decides on the scope of the project. The role of the project manager is to see that the process is followed and that obstacles are removed.
That's not to say that a project manager has to be following agile to be a servant leader. Really, any leader can follow the servant leader model. They just need to be aware of opportunities where they can serve the team in order to further to goals and vision of the team. In the words of Lao Tzu, "The greatest leader forgets himself and tends to the needs of others."