FORTH/ICE-HT, under the chairing of Principal Researcher, Dr. Maria I. Klapa, Metabolic Engineering & Systems Biology Laboratory, organizes the 1^st ELIXIR Fluxomics training school 2021, in the context of the ELIXIR Metabolomics Community-led Implementation Study “Standardizing the fluxomics workflows”. The school is supported by the European Infrastructure for Biological Data Management and Bioinformatics ELIXIR. It is a 5-day school to take place virtually in the week of October 4-8, 2021. The purpose of the training school is to provide an introduction to fluxomics, a biomolecular analysis used in a variety of life science research applications, from microbial biotechnology, agri-food / toxicology, to biomedical research and the design of drugs and therapeutic treatments. The school trainers are eminent scientists in the field of metabolomics and metabolic flux analysis, from EU and US. The school will be attended by 22 students from 9 European countries and USA.