Michael Kreuzer, Professor for Animal Nutrition at the ETH Zurich and Vice-President of the North-South Centre, delivered the opening speech “About the World Food System” of this year's Tropentag. Being held for the first time outside Germany, the Tropentag just beat the records: There are 1.228 registrations from a total of 83 countries, more than 1.100 abstracts were submitted, of which 522 were accepted for presentation, and there will be 130 oral presentations and almost 400 poster presentations. Thus, it promises to be a very diverse, multi-faceted and interesting conference! The World Food System is a major area of research of the North South Centre of the ETH Zurich. Founded in 2007 from its predecessor, the Centre of International Agriculture (ZIL), the North South Centre brings together various academic disciplines, ranging from agricultural sciences and information technology, to environmental studies and social sciences, thus offering an interdisciplinary approach for analyzing the World Food System. In short, the World Food System encompasses all natural resources involved in food production for feeding mankind. This system is shaped by global and local factors, ecological influences, man-made policies and technologies and consumption patterns. Analytically, the concept of the World Food System operates with four major categories: availability of food, access to food, different usages of food (feed, fuel, fibres) and stability of food catering. These days, the World Food System is beleaguered by several major challenges, of which the most severe are food scarcities, questions of food safety, diet changes, environmental degradation and climate change. The Tropentag will deal with many of these issues, thereby elaborating the state of the World Food System and its local manifestations with regard to food security and food safety.