Colombia has a number of metropolitan areas, each composed of an urban center and its associated municipalities. Some of these are officially designated administrative and census areas, while most of them are not officially defined areas or administrative regions.
The following criteria must be met for a group of communities to be designated a metropolitan area:
Commuting to work is a major characteristic of a metropolitan area. As a result, the secondary cities are often called "dormitory cities"; meaning places where the inhabitants only go home to sleep.
An important function of the officially designated metropolitan areas is to provide for joint planning between the municipalities, thereby managing ordered and proportional economic growth according to the necessities of the area and the physical characteristics of each municipality.
The following metropolitan areas are currently recognized by the Colombian government (as of 2007):