Cyprinus carpio is a widespread freshwater fish. The native wild populations are considered vulnerable to extinction by the International Union for Conservation of Nature (IUCN) and included in the list of the world's 100 worst invasive species. However, although C. carpio is the oldest reared species and currently the number one in aquaculture, there is limited information available about this species in natural conditions. Further research is also needed on current farming conditions as well as aggregation and aggression behaviour in the wild and in farms. In addition, escape of farmed carps should be avoided in order to prevent fish welfare impairment of wild populations. Furthermore, carp welfare can be improved using extensive culture systems promoting a natural habitat and behaviour of the species.