The complexity and magnitude of socio-economic problems confronting societies throughout the world transcend the capacities of any single sector – business, government or civic. Dealing with them effectively calls for creative collaboration across sectors. Such partnering has begun to emerge and holds significant potential as a powerful organizational modality for contributing to societal well-being. Cross-sectoral collaboration will become a primary transformational vehicle in this century. Creating such alliances requires significant leadership. This chapter will explore and illustrate why and how business leaders and their companies are forging social purpose partnerships.