What makes a leader great? People have wildly different answers to that question. While there may not be one black and white answer, we can certainly look at the most common types of leaders and see what makes them so effective. In 2000, Daniel Goleman did a study on leadership styles that garnered the best results while taking emotional intelligence into account. Four of the leadership styles resulted in positive impacts on the workplace environment. Let’s take a look at these types of leaders and see how they might improve further with the application of some servant leader concepts.