An integrated flood risk management (IFRM) strategy consist of a comprehensive set of measures to reduce the risk: protective measures (to reduce the probability of a flood), and land use planning and disaster management (to reduce the consequences of a flood. In the Netherlands this is called a ‘multiple layer safety approach’, other countries refer to ‘multiple lines of defence’. In the development of IFRM strategies one of the main challenges is to define the contribution of disaster management to the reduction of risk, especially when experience with floods is rare and flood awareness is limited.@en