Hans van Ammers studied Physical Geografy at the University of Utrecht (Nl) and started his carrier at a consultancy investigation soil contamination. His next steps were set at the municipality of Arnhem, capital of the province of Gelderland in various positions all related to the physical living environment: water, sewage and public space. Since 2003 he has been active in various European subsidy programmes. In 2008 he became the projectmanager for Arnhem in the European Interreg subsidyproject called 'Future Cities' facing the consequences of climate change. The focus of Arnhem was to investigate the city climate in Arnhem and the City Region Arnhem Nijmegen and determine the consequences of upheating for the city and its inhabitants. Based on that survey Arnhem became in 2012 one of the first cities in the Netherlands with a policy and ambition to improve the city climate regarding to heat stress with focus on outdoor and indoor upheating linking heat stress to health. Since that time city climate, reducing heat stress and the added value of green has been more and more 'taken into the heart by the city council, residents groups and organisations in the Arnhem region, giving the green character of Arnhem another dimension. In the approach the linkage with reducing the effects of storm water runoff is evident.