A district creates basic conditions of living: It provides resilient structures, public space which is respected and creates space for encounter – or distrust and isolation-promoting ghettos. Feeling integrated and secure and having good contacts in the neighbourhood also creates life quality. Ecological measures that only rich people can afford are not sustainable because they create social division. Sustainability also means creating access to vital life resources for everyone. Only this makes fruitful cooperation possible, and faithful and positive exchanges – both materially and spiritually. Thinking in this direction means to invest in the future. Concepts of social sustainability have been successfully implemented in Freiburg.