The RETHINK big Community consists of European companies (looking closely at SMEs) as well as all projects, organizations and initiatives that bring together research and industrial Big Data communities. Ultimately, RETHINK big aims to establish a Big Data Technology Ecosystem that includes the key European hardware, networking, and system architects, the key European producers and consumers of Big Data that cooperates with key European projects and initiatives in the area of Big Data, HPC, and ICT in Europe, such as the NESSI, the European Data Forum, The European Technology Platform for High Performance Computing as well as as the Graphene Flagship, Human Brain Flagship, Big Project among others.