The idea of social entrepreneurship has struck a responsive chord. It is a phrase well suited to our times. It combines the passion of a social mission with an image of business-like discipline, innovation, and determination commonly associated with, for instance, the high-tech pioneers of Silicon Valley. The time is certainly ripe for entrepreneurial approaches to social problems. Many governmental and philanthropic efforts have fallen far short of our expectations. Major social sector institutions are often viewed as inefficient, ineffective, and unresponsive. Social entrepreneurs are needed to develop new models for a new century.