Abstract. The classic aid in operative flood defence is the sandbag. Over the past few decades, though, so-called sandbag replacement systems (SBRS) have also been available for flood fighting. Although the use of sandbags is time-consuming as well as highly intensive in terms of materials and personnel, so far SBRS are rarely used in Germany. However, owing to their functionality and their labour and time-saving characteristics, they can make an essential contribution to flood protection – and this all the more so in view of the expected consequences of climate change. In order to foster confidence in such systems, the Institute of Hydraulic Engineering at the Hochschule Bremen – City University of Applied Sciences (IWA) carried out a series of systematic tests of SBRS that focused on the functionality, stability and handling of the systems. The experience gained shows that SBRS have the potential to make flood defence more efficient than the use of sandbags alone. Since SBRS are technical systems whose functional capability must be proven before they can be used, it is recommended to introduce an official test and certification procedure.