The analysis of the population’s linguistic competence in Euskera uses the knowledge of Euskera as declared by the population. The Population Census offers characteristics of knowledge of Euskera of the population such as the mother tongue or the language spoken at home by municipality, as well as the evolution of the overall level of Euskera by province. The objective of the Sociolinguistic Survey of Euskal Herria (ESE) is to know about and monitor the current situation of Euskera, breaking down the linguistic information of Euskal Herria between the three provinces of the Basque Country, Navarre and Iparralde (French Basque Country).