Only considering that the building sector generates nearly 40% of annual global CO2 emissions (UN Environment, IEA. Global Status Report 2017, 2017) may probably be enough to justify the presence of an « architecture » entry in this Handbook of the Anthropocene. Yet this article broadens the question to clarify both what is behind the complex concept of « architecture » and in which sense it may be a key point if «our job is to make the Anthropocene as short/thin as possible » (Haraway D. Staying with the trouble: making Kin in the Chthulucene. Duke University Press, 2016: 100). Assuming it is not « too late », the article will then try to show how architecture, despite its disastrous past achievements, could paradoxically become a fantastic way to shape truly ecological societies.