Path-goal theory specifies that leader behaviors should complement rather than duplicate the characteristics of followers’ work environments. There are three kinds of environmental contingencies: task structure, the formal authority system, and the primary work group. As in Fiedler's contingency theory, task structure is the degree to which the requirements of a subordinate's tasks are clearly specified. When task structure is low and tasks are unclear, directive leadership should be used because it complements the work environment. When task structure is high and tasks are clear, however, directive leadership is not needed because it duplicates what task structure provides. Alternatively, when tasks are stressful, frustrating, or dissatisfying, leaders should respond with supportive leadership.