In several Latin American countries, a cadena nacional (Spanish for national network; plural cadenas nacionales), also referred to as a cadena oficial (Spanish for official network) or red voluntaria (Spanish for voluntary network) is a joint transmission through the media, generally radio and television stations, which aims to reach the largest number of inhabitants of a State. These types of broadcasts are usually of a political nature, since they are mostly messages from government authorities about different matters of general interest, as well as the transmission of electoral debates for the elections to the executive power of each country.
The institutional characteristics of the national chain vary according to the legislation and customs of each country. It may be a resource officially provided for in legislation or the name may be used informally, to describe a coordinated transmission. The coupling of the different media to the signal of the official chain can also be voluntary or compulsory. Similarly, the national network can be used for different types of transmissions in addition to the official messages of the State authorities.