Flood risk assessment is an important and complex task requiring various data sources and multi-factor analysis. Many studies have considered various factors in flood risk assessment, i.e. physical as well as socio-economic factors and preventive actions. The following instructions focus on the potential harm due to geographical and meteorological factors, often described as flood hazard. In this short introduction to flood hazard mapping, we only make use of a small number of data sources to allow application in cases where sufficient data is lacking. - The project on which this technical instruction is based, was funded by the Federal Ministry of Education and Research of Germany under funding number 01LE1804B1.