This research paper is a study on parasitic strategies in Biology and Architecture. Parasites constitute an extremely important species for the sustainability of ecosystems. They have survived for over 7000 years on the planet and their existence is responsible for the current evolution of many organisms. Through successive conflicts, they have evolved mechanisms and characteristics to ensure their survival and the balance of biodiversity. By studying their mode of action and the connections that develop between parasite-host, the aim is to find analogies at the level of architecture and the city. Drawing on features from biology, reflections emerge on the importance that artificial 'parasites' could have in the urban fabric and the relationships that are formed within it.