Transient Defence Measures (TDM) are defined as actions that can be taken in advance in the coastal zone in order to reduce the impacts of an specific forecasted storm event. The design of such transient works requires detailed information of the hydrodynamic conditions of forecast events and an assessment of the effect on subsequent beach evolution. In this work, we present an analysis through numerical modelling of the efficiency of transitional dunes and temporary low-crested breakwaters considering the Mediterranean hydrodynamic conditions. The outcomes will serve to design a set of alternatives for mitigation of the coastal risks caused by extreme waves and high sea water levels in European coastal areas.