"Elementary processes in molecular switches at surfaces" is the title of a large research center at our department. Experimentalists and theoreticians work together with chemists and physicists from other universities and institutes to understand the properties of switchable molecules and their interaction with solid surfaces. The research center is an excellent example of the interdisciplinary nature of modern science. The idea of this advanced student seminar is to introduce research topics and challenges that are tackled within the research center. We will first set the general framework by studying molecular switches, their occurrence in nature and potential application. From there we will move to the interaction between an extended solid-state system and a large molecule. The projects pursued by research groups within the center will be presented. A general introduction into a project will be juxtaposed a specific paper and example of recent work. Since this is the first seminar series of this type, the talks will focus on projects lead by groups at the physics department (Brouwer, Franke, Kuch, von Oppen, Reich, Weinelt). The seminar will be an excellent opportunity to learn about a major research topic in our department. We also welcome advanced Ma and PhD students who work on a project in the research center and want to get an overview over the other projects. To earn credits you will present a scientific talk of 30-40 mins followed by a discussion.