Robert K. Greenleaf published two posthumous essay collections (available at Greenleaf.org). Today scores of colleges and universities include Servant Leadership in their curricula and hundreds of companies embrace Greenleaf's philosophy. As Greenleaf strived to serve through education, he became the leader of a movement. Bass, B. M., and Stogdill, R. M. (1990). "Bass & Stogdill's Handbook of Leadership: Theory, Research, and Managerial Applications" (3rd ed.). New York:Free Press. Frick, Don M. (2004)." Robert K. Greenleaf: A Life of Servant Leadership." San Francisco: Berrett-Koehler Publishers. Greenleaf, R.K. (2003). "The Servant-Leader Within: a Transformative Path" New York: Paulist Press. Greenleaf, R. K. (2002). "Servant Leadership:
Robert K. Greenleaf the needs of followers are holy and legitimate, and the leaders use of power arises from the consent of the followers. Greenleaf was very focused on action and ends, and he held a Sabbath attitude about organizational life. Like Christ, who said “The Sabbath was made for man, not man for the Sabbath” Greenleaf believed that institutions should serve people. He also felt that he was on the threshold of an important historical moment, of a paradigm shift in the collective American response to formal authority. "A fresh critical look is being taken at the issues of power and authority,