Mark van Loosdrecht is Professor in Environmental Biotechnology at Delft University of Technology, The Netherlands. He graduated from and did his PhD research at Wageningen University. His PhD topic was a combination of microbiology and colloid chemistry. He was appointed at Delft in 1988 and became Full Professor in 1998. His research is characterized by the combination of scientific understanding of complex systems and development of new processes. Dr. van Loosdrecht’s scientific interests are mainly related to biofilm processes, nutrient conversion processes and the role of storage polymers in microbial ecology. In particular, he is interested in new processes related to wastewater treatment and resource recovery. His research has resulted in several processes currently applied on full scale such as the Sharon process, Anammox process and Nereda process. He is Editor in Chief of Water Research. He obtained several prizes for his work, including the Lee Kuan Yew Singapore Water Singapore Prize, NWO Spinoza Award, STW Simon Stevin Award and the IWA grand award. He is member of the Royal Dutch Academy of Arts and Sciences, the Dutch Academy of Engineering (AcTI) and the USA National Academy of Engineering. He was awarded a knighthood in the order of the Dutch Lion and honorary doctorates from U-Gent and ETH-Zurich. He has published over 700 scientific papers, has 20 patents and has supervised over 50 PhD students. In 2018, he received the Stockholm Water Prize.