Nature based solutions have been identified as a key strategy to multifunctional land use. Most `water sensitive´ urban design strategies aim to retrofit centralized infrastructure as temporary relief to flooding incidents rather than as holistic measures. The principal approach of the Sponge City System (“Schwammstadtsystem”) is working with rainwater rather than only defending against it. The novel transdisciplinary ideas lie in providing comprehensive benefits to the urban environment in view of climate change by combining responses to urban flooding with water retention and evapotranspiration via trees for urban cooling. The Urban Sponge City System is often referred to as the "Stockholm system" following the publication of a handbook on the system for the city of Stockholm by Embrén, Alvem, Stal and Woodward. There the system was promoted as a response to urban flash floods and a measure to avoid costly extensions in sewer systems. The system is a design strategy for a coherent and integrated approach towards climate change resilient cities that can be implemented step by step. It combines the three different approaches of ● improvement of local urban heat islands (UHI) by adiabatic cooling by evapotranspiration via urban trees ● site improvement for street trees by structural soils providing water and air in the root zone ● rainwater (stormwater) retention directly on site in the streets. The aim of the group is to introduce and develop the Sponge City System as Green Infrastructure (GI) in urban surroundings in Austria. The main goal is to establish healthy urban trees as an effective action against UHIs and to simultaneously create an alternative to conventional drainage. The intrinsic nature of landscape architecture and urban design on the one side and engineering approaches on the other side often hinder a move towards holistic solutions. In 2018 a group of practitioners, teachers and researchers formed the Sponge City Austria Working Group under the organisational roof of OEGLA, The Austrian Association of Landscape Architects. The working group acts as an Austrian network and fosters exchanges: The members in a transdisciplinary group inform and coach each other. The group coordinates projects and project ideas that correspond to the principles of the sponge city system under different framework conditions as field trials in Austria. The working group has promoted and assisted or observed sponge city projects in Vienna, Graz and Innsbruck. Obstacles are identified and possible answers are discussed. Obstacles are for instance ● the different goals and design cultures in the disciplines involved ● legal requirements and standards for the disciplines involved ● practice on the construction site in civil engineering The working group will present its finding and examples. It seeks contacts and information on an European level for finding and exchanging practical solutions under different conditions.