Five design principles for social entrepreneurs at the base of the pyramid from Paul Polak
These are the common features of initiatives that have truly helped extremely poor people move out of poverty:
1) They begin by thoroughly listening to poor customers and thoroughly understanding the specific context of their lives.
2) They design and implement ruthlessly affordable technologies or business models.
3) Energizing private sector market forces plays a central role in their implementation.
4) Radical decentralization is integrated into economically viable last-mile distribution.
5) Design for scale is a central focus of the enterprise from the very beginning.
This is the short list, Paul’s 12 problem solving principles goes far more in depth, but a great start.