Green infrastructure is one of these ecology-based complex concepts… and an interesting one. The traditional concept of infrastructure (“gray infrastructure”, as it is called these days as green ones have appeared) is that of any kind of contraption that allows you to use the laws of physics or any other science to adapt the current environment to our needs as a species; it is usually based on active elements that somehow require high amounts of ressources and some kind of maintenance. Green infraestructure is presented as an approach in which the man-made intervention is less visible, with an aim to get a good level of environmental services (yes, she is still the client…) by working in a more symbiotic way with ecosystems; understanding how nature works helps achieve a higher efficiency in some aspects with less pollution and environmental damage (not that previous engineers were brutes, but they worked from a different paradigm). The European Environmental Agency booklet conveys that idea in a more ellaborate way.