Our PV research activities are focused on the physics of organic and, more recently, hybrid perovskite photovoltaics. Perovskite photovoltaics is a relatively new type of thin-film PV technology, which experienced a tremendous increase in power conversion efficiency from 4 % to above 25 % within the last 10 years. Organic solar cells also developed tremendously and demonstrated efficiencies in the range of 18%. Our PV group activities at EP6 aim at understanding the fundamental working principles of organic and hybrid perovskite solar cells, such as charge carrier transport, charge carrier extraction as well as the recombination dynamics of charge carriers. Another important related topic is the analysis of structural defects and dopants in organic and hybrid semiconductors and their impact on the optoelectronic and photovoltaic performance. Many different complementary techniques are available to probe cw- and transient optical and electrical properties of active layers as well as fully processed solar cells. Lab scale devices can be easily made from solution as well as from vapor phase in our laboratories, whereas larger scale devices, e.g. produced via roll-to-roll printing, are also available.