They are in constant transformation and need to satisfy people's basic needs, such as housing, living, schools, clean water, hospitals and safe and reliable transport.
Nad on pidevas muutumises ja peavad toime tulema inimeste põhivajaduste rahuldamisega, nt eluasemed, elukeskkond, koolid, puhas vesi, haiglad, ohutu ja usaldusväärne transport.