We will provide the first-ever research training in the transdisciplinary area of Microbial Resource Management and Engineering (MRME) to develop new concepts and technologies to meet the imminent societal challenge of closing the Urban Water Cycle (UWC), the sustainable management of residual waters and the preparation and distribution of safe potable water.The network consists of 10 regional world-leading Network Partners (NP) from private and academic sectors in DK, BE, UK, PT, CH, SE, complemented by 8 associated partners. Transdisciplinary training of 13 ESR and one ER will span from (molecular) microbial ecology to environmental engineering. Each ESR develops a personal and professional development plan. Training elements include expert training through cutting-edge individualized research projects, cross-sectoral mentorships, private sector internships, and participation in Network-wide PhD schools. Schools alternate between professional and technical training. The ITN ends with a fellow-led international research symposium. A supervisory board tracks project implementation. The private sector is engaged at the highest level: 4 private partners are full NPs.The ITN will provide ESRs with transsectoral training and experience, and instill an aptitude for research valorization, to create opportunity for research careers in public and private sectors. This ITN is timely, significant, and unique, as scientific and technological advances create tremendous opportunities for MRME, training in this transdisciplinary area is essentially absent across EU, and the need for innovation in closing the UWC is pressing, as water resources dwindle, urban consumption grows, and existing infrastructure ages.The ITN will structure the European research area and strengthen ties between and within the academic and private partners across regions. Researchers will be trained at the highest level with job prospects across academic, private, and public sectors.