Access to electricity is a requirement for economic and social development. In the world 1,577 million people live without access to electricity. Private organisations in India, Tanzania and Brazil offer solar home systems to households without electricity access. This thesis investigates some of the many challenges which solar home system providers are facing. A country and a case study comparison shows that some of these key challenges are in making their systems affordable, sourcing components, financing consumers, educating customers and staff, providing a maintenance service, working profitably and growing sustainably.