The main conclusion of this modelling exercise would be that useful results can be obtained with all models starting from the same input regarding the soil and strength parameters of the dike. However, in some cases foreknowledge is needed when executing the simulations as well was interpreting the results. In addition, as most models take only a (limited and sometimes different) set of breaching mechanisms into account, the use of today’s state-of-the-art breach growth models is not (yet) dummy proof. Whether and how retrograde surface erosion and/or upstream headcut migration are accounted for will have an important influence on the timing of the peak flow through the breach. Furthermore, even when stated that block failure is included in a model, a stepwise increase of the breach width is never observed in the model output due to implicit assumptions in some models.