The open cabildo (Spanish: cabildo abierto) was a special mode of assembly of the inhabitants of Latin American cities during the Spanish colonial period, in case of emergencies or disasters. Usually, the colonial cities were governed by a cabildo or an ayuntamiento, a municipal council in which most of the officers were appointed by the authorities. In cases of emergency, the cabildo could convene the heads of household (vecinos) in an "open" cabildo.
At the beginning of the Spanish American wars of independence open cabildos played a decisive revolutionary role, acting as organs of popular participation, as they were able to remove the colonial authorities and establish new autonomous governments.
In modern times, some Latin American countries have used the name "open cabildos" for public assemblies convened by municipal governments to decide local matters of public importance. The term is sometimes used for present-day public meetings to make decisions.