Alliances and partnerships have long played a prominent role in the business world, but have only recently begun to receive greater attention by the providers of microfinance services. In recent years, several innovative business models based on linkages between organizations, often supported by new technology innovation, show promise to substantially change the way financial services are delivered to the poor, both in terms of scale of outreach and increased diversity of services offered. But what are the implications of this for both the service providers and their clients? What are the pitfalls and constraints? And how might these best be managed? This paper addresses these questions.