The geomorphological and ecological response of the ebb tidal deltas of the SW Netherlands to implementation of the Delta Project during the last decades, has been the subject of an integrated research project. General observed geomorphological trends are: erosion of the delta fronts and of the relic tidal bars in the landward parts of the deltas, and sedimentation in the tidal channels and in longshore bars at the edges of the deltas. Ecologically, a general trend towards richer benthic fauna communities is observable. The integrated approach in coastal research combining geomorphological analysis of field data with numerical modelling, and integrating hydraulic, geomorphological, sedimentological and biological data, has appeared very promising. Progress in this field would be stimulated by further research of the driving processes in the interaction of hydrodynamics - sediment - biota. The level of detail (spatial and temporal)' in geomorphological contributions to such research will have to be much higher than usual in current coastal morphological studies.