Research and development of photovoltaic solar cells is playing an ever larger practical role in energy supply and ecological conservation all over the world. Many materials science problems are encountered in understanding existing solar cells and the development of more efficient, less costly, and more stable cells. This important and timely book provides a historical overview, but concentrates primarily on exciting developments in the last decade. It describes the properties of the materials that play an important role in photovoltaic applications, the solar cell structures in which they are used, and the experimental and theoretical developments that have led to the most promising contenders.