Arjen Luijendijk is an expert in the field of modelling morphological impacts of coastal developments. At Deltares Mr. Luijendijk gained experience in working with advanced numerical modelling techniques in the field of tides, sediment transport, density driven flows, waves, wave-current interaction and coastal morphology. His present role is as senior researcher and advisor in specialized consultancy projects regarding coastal developments. At the department of Harbour, Coastal and Offshore engineering Mr. Luijendijk is coordinator of the Coastal Engineering market team and related research topics. Such coastal engineering R&D projects include studies on the numerical modeling on aggregated time and spatial scales, but also tool development such as coastal design tools combined with methods to quantify uncertainty in model predictions. In addition, Mr. Luijendijk gained experience in a series of climate change studies and publications, e.g. Mississippi Coastal Restoration project and several studies on the stability of small tidal inlets. From the start of Building with Nature in 2008 Mr. Luijendijk has been involved in the innovation programme, where he was responsible for developing an eco-morphological model for mega-nourishments and developing integrated tools for long-term coastal developments. Mr. Luijendijk is an ambassador of the Next Generation Hydro Software project and has been responsible for the initiation and steering of the Delft3D Open Source Community. In 2013, Mr. Luijendijk started his research at Delft University of Technology on the physical feasibility of mega-nourishments worldwide. His research focusses on developing a seamless modeling approach for morphodynamic modeling.