As one of the largest unsubsidized markets for solar home systems (SHSs) in the world, Kenya represents a promising model for rural electrification based on private purchases of clean decentralized photovoltaic technologies. Small amorphous-silicon modules dominate the market and most brands provide high quality and affordable service. Product quality varies widely. however, and the public has limited capacity to distinguish among competing brands. This imposes direct hardships on households with the misfortune to purchase low-quality equipment. and it constrains sales as some customers refrain from purchasing solar equipment due to the associated performance uncertainty. This article analyzes market failure associated with photovoltaic module quality in the Kenyan SHS market and develops strategies to address the problem-emphasizing that similar quality problems may exist for other SHS components and in other markets. The principal conclusion is that domestic product testing with public disclosure represents an inexpensive low-risk strategy, but it may prove inadequate. Mandatory product quality standards based on international testing regimes (e.g. IEC standards), augmented with a basic domestic testing option. would provide stronger assurance. but the risks associated with this intervention suggest caution. An emerging multilateral SHS market support effort (PVMTI) should ensure quality for the credit-based sales it promotes in Kenya; however, the long-term impact of this approach is not yet clear and it is unlikely to address quality problems associated with the existing unsubsidized sales-based markets for SHSs. Finally, fee-for-service models would decisively address quality problems. but launching this model in the Kenyan market would likely require large subsidies.