Unlike traditional energy-production technologies that have ongoing consumables costs, nearly all of the costs of photovoltaic (PV) systems must be paid at the beginning. Reducing those initial capital costs is crucial to reducing the cost of solar electricity. In addition to module price, many factors contribute to the price of a PV system, including installation labour, power electronics, permitting and other regulatory costs, and in the case of ground-mount systems, site acquisition and preparation costs. This book presents detailed, bottom-up 2010 benchmark system prices for residential and commercial rooftop systems and utility-scale ground-mount systems. The difference between the evolutionary projections and SunShot targets highlights the need for innovative system designs and installation methods to complement module-level cost reductions.