Professor in Paediatric Intensive Care, and Head of the Paediatric Intensive Care Unit (PICU), at the Emma Children’s Hospital, Amsterdam UMC. JvW, worked in 1991-1992 for Medicine Sans Frontiers (MSF) in a refugee camp on the Thai-Cambodian border, conducting mefloquine trials in (severe) malaria. In addition, in 2007 he worked in an MSF project in Myanmar. JvW supervised studies in Kenya and Uganda regarding fluid management during shock in malnourished children. He is member of the board of directors of Medical Action Myanmar. Finally, he is involved in a collaboration programme with the Mercy James Center in the Queen Elisabeth Central Hospital, Blantyre, Malawi where he is co-investigator in studies on fluid management in sepsis in children.