Some countries can be considered to have multiple capitals. In some cases, one city is the capital for some purposes, and one or more others are capital for other purposes, without any being considered an official capital in preference to the others. There are also cases where there is a single legally defined capital, but one or more other cities operate as the seat of government of some or all parts of the national government; in these situations, sources may disagree on whether these other cities are considered additional capital cities.