Recent tsunamis have demonstrated the tremendous power that nature can unleash. Steps must be taken to protect sensitive coastal areas against damage: the construction of artificial reefs is an optimal solution since it minimises ecosystem impacts. The Everans project used numerical modelling to address a number of critical issues regarding artificial reefs. In order to understand how artificial reefs stand up to extreme waves like tsunamis, a physical model was built in the laboratory. The data collected was then used to develop new code for a common computational fluid dynamics wave model. Testing of the model was performed with real data collected in the field. The model was also exploited by the Everans scientists to investigate other important phenomena that affect artificial reefs, including wave pumping and wave-driven currents. Several recommendations concerning reef geometry and permeability have resulted from these simulations. The aim is to improve durability while still protecting the shoreline from erosion. These results are being shared with the research community through a number of publications and conference presentations; they will help to keep coastal areas with artificial reefs safer in the future.