Tomasz Zylicz is Professor in Economics at the University of Warsaw (Poland). He received his PhD in economics at the University of Warsaw. Prior to joining Warsaw University, he worked as the director of Economics in Poland's first post-communist Ministry of Environment. He was responsible for the state environmental budget and served as a co-author of a major environmental policy reform. In 1993, he received the "Pew Scholar Award in Conservation and the Environment". He used the award to create the Warsaw Ecological Economics Center at UW. The Center carries out research on economic aspects of environmental protection as well as hosts fellowships for young scholars. He specializes in research on the valuation of services provided by urban ecosystems. In particular, he is interested in valuing the benefits provided by urban trees in terms of air purification, carbon sequestration, reduction of excessive surface water runoff, air cooling, biodiversity enhancement, improvement of urban space aesthetics, and creation of conditions for recreational activities.