The photovoltaics industry is growing at a remarkable rate, more than 35% per year for the past 8 years. This reflects both the recent enlightened favourable rebates and tariff policies in several European countries and Japan but also the growing awareness of energy security and greenhouse abatement imperatives. This rapid growth is mirrored by an intense research effort which critically depends on materials research, with several complex ternary, quarternary inorganic materials being used and a raft of new organic and molecular materials as well as a growing importance of quantum confined nanostructures, which allow extra degrees of freedom in tailoring materials properties.