was trained as a biologist. Her first job was with the Centre of Energy Conservation, evaluating the consequences of energy scenarios on the natural environment. After that, she has been employed as a researcher at the Institute of Environmental Sciences (CML) at Leiden University. She has conducted research that for the most part can be placed under the heading of Industrial Ecology. Research areas are, among others: stock breeding and the ammonia problem, risk assessment, life-cycle assessment, biodiversity policy, natural resource accounting, indicator development, material flow accounting, and especially substance flow analysis. She still is employed at the CML as an Associate Professor and is now the head of CML’s Industrial Ecology Department. She has initiated CML’s MSc program in Industrial Ecology and is active in that program as a teacher and as the chair of the Educational Committee. She participates as a senior researcher in many EU-projects on environmental impacts, on resource efficiency and on eco-innovation. She is active in the International Society for Industrial Ecology, presently as Associate Editor of the Journal of Industrial Ecology. In the International Resource Panel, she has contributed to the “Priority Products and Materials” report and is principal author of the “Environmental challenges of anthropogenic metals flows and cycles” report.