EUREC4A has attracted a lot of international attention. In addition to HALO and ATR-42 two additional research aircraft and four research vessel will join the campaign as additional platforms. The ships will host numerous autonomous observing systems of the atmospheric boundary layer or the ocean. The measurement setup is displayed in Fig. 3.22. The large international attention is also recognized by The World Climate Research program (WCRP), which has endorsed EUREC4A as capstone experiments of the Grand Science Challenges on Cloud Circulation and Climate Sensitivity. In parallel EUREC4A has become the nucleus for other related scientific activities that intend to join the experiment and will enrich the data set: EUREC4A-OA/ATOMIC (European Ocean-Atmosphere component of EUREC4A / Atlantic Tradewind Ocean- Atmosphere Mesoscale Interaction Campaign by the US) will coordinate the four research vessels. They will observe ocean state and exchange fluxes and will serve as platforms for ground based remote sensing and in-situ profiling by radiosondes of the cloudy atmosphere. EUREC4A-ISO will explore the water isotope signature and help to disentangl the various processes affecting the water budget of cumulus clouds. EUREC4A-Wind will bring together investigators from different institutes to promote a better understanding of the coupling of winds, convection and clouds and their importance for weather and climate prediction in the trades. In particular, this initiative will explore and validate the potential of the ESA ADM-Aeolus mission. EUREC4A-Model will accompany the campaign with high-resolution numerical simulation with a grid spacing of 1 km or less using the ICON model and link the campaign with most recent cutting-edge initiative of cloud resolving global models (cf. Dyamond project, www.esiwace.eu/services/dyamond).