Here is a good, brief summary over at the Wall Street Journal of six different leadership styles, as summarized by Daniel Goleman (author of Emotional Intelligence and Primal Leadership: Learning to Lead with Emotional Intelligence). The six styles are:
“The most effective leaders can move among these styles, adopting the one that meets the needs of the moment.” However, some of the styles need to be used very sparingly.
I think that these six styles probably do not capture the full range of useful leadership styles, but this is a helpful initial context.
A good summary of the five tasks of the manager that Peter Drucker specified.
CJ Mahaney’s 17-part series on biblical productivity is now available all together in pdf format. He takes an approach similar to Covey’s roles > goals > schedule model, which I bake into my GTD-Covey synthesis (with some modifications).