The 2005 General Census, carried out over a year (22 May 2005 to 22 May 2006) has been considered an example for the world by different experts, such as  José Luis Cervera, international consultant for official statistical projects for the European Commission and the United Nations, and Pilar  Martín Guzmán, former director of the National Statistics Institute of Spain.

See technical manual of the 2005 Census