For the purpose of reducing census costs and decreasing the workload of informants to a minimum, the data collection is being carried out in three different phases.

The first phase was carried out between 1 October and 31 December 2009. Agrarian owners have received, via post, a census questionnaire for each one of the agricultural and/or livestock operations that they own, together with instructions for their correct completion. The completed questionnaire has been submitted to the INE in the pre-paid envelope included with the census documentation sent. It was also possible to complete it online at the address provided, until 28 February 2010.

The second phase has been carried out since 1 January 2010. For this phase, which complements the first phase, computer-assisted telephone interviews are being conducted, either to complete the census questionnaire directly or to contrast data from the questionnaire completed in the previous phase.

Simultaneously, since 1 January 2010, in-person interviews are being conducted with those owners who have been selected in a random sample to collect complementary data regarding the production methods of the agrarian operations.

All of the information provided will be protected by Statistical Secrecy (Law regarding Public Statistical Function of 9 May 1989, BOE of 11 May 1989), implying that it may only be used in an aggregate manner, without including any reference of an individual nature. In turn, Law 13/1996 (BOE of 31 December 1996) determines the compulsory nature of the completion of the census questionnaire.