You are invited to participate in the 11th International Conference on Hybrid and Organic Photovoltaics, from 12 to 15 May 2019. For this 1edition of the HOPV conference we will return to Rome, Italy. In these past ten years hybrid and organic solar cells have advanced enormously in terms of efficiency, lifetime, and technology and have a true promise to become an important source of renewable energy. In addition, they present fascinating opportunities and challenges for scientific research and technological development. The main topics of this conference are the development, function and modeling of materials and devices for hybrid and organic solar cells, including perovskite solar cells, organic solar cells, quantum dot solar cells, and dye-sensitized solar cells together with their integration into devices for photolelectrochemical water splitting. Building upon success of the previous HOPV conferences, the conference will provide an excellent opportunity for scientists and engineers around the world to discuss the latest developments in hybrid and organic photovoltaics. The conference will be led by world leading invited speakers covering a broad range of the latest scientific advances in morning plenary sessions. The conference encourages presentation of oral as well as poster contributions from scientists from all over the world, which will be presented in four parallel sessions running in the afternoons. Just submit your abstracts before the deadline, which is strict. Special attention is given to the poster contributions.