The Aspern Urban Lakeside is one of Europe’s largest current urban development projects. Over the next 15 years, a new center for living and working which combines nature and urbanity will be built in Vienna’s east. The new buildings will be situated in an extensive park centered round a 50.000 sq. m. artificial lake. Together with Delta ZT, AllesWirdGut planned a residential and shopping complex of 23.000 m² gross floor space in the Aspern Urban Lakeside. The project is comprised of five buildings of apartments and shops. Outwardly, the built ensemble presents itself as a varied urban space. Inside, the focus is placed on social interaction and the quality of living. The planning provides for variable possibilities of use which also anticipate future needs. The different apartment types are multiply adaptable to account for different family situations and stages in life. The interior of the buildings includes wide stairs inspired by the staircases of Viennese Historism. They provide access to about 35 apartments. This type of circulation infrastructure keeps maintenance costs low and facilitates communication between residents. AllesWirdGut followed a “House of Life” concept which provides for a house community of some 100 people, about half of them older and half young. Contact and synergies between occupants are wished-for here and considered and promoted already in the planning. The entire publicly accessible inner courtyard of the building ensemble is lifted by one floor and greened with trees and planting. This green area connects the five houses and is also accessible over barrier-free ramps. Shaded benches, nice quiet spots amid the urban bustle, again enhance the quality of life and promote exchange between residents. Due to its compact volume and the economic use of materials the project is ecologically sustainable. The window surfaces are optimized for daylighting. There is district heating, all taps and fittings are water-saving, and building services are intelligent, yet simple and hence low-maintenance. Finally, building certification ensures that ecological requirements incorporated and implemented in the planning, tendering procedures, and construction throughout the entire building process. All in all, this mixed-use five-building project is in full congruence with the seminal urban-development objectives pursued at Aspern.