This section was created in 1990. Previously, the National Historical Archive had taken occasional specific action on different fonds of the Archive. Since 1991, there is a plan of action for the preservation of the archival material, which is structured along two main lines: the preservation of the fonds (material measures: conditions of preservation of depots, disinfection, etc., and microfilming), and restoration of items according to their condition or according to criteria of historical and cultural importance, and in the case of unique items.

The line of action, when carrying out the management in the section, is to restore the largest possible part of the documentation in the workshop of the National Historical Archive. When the quantity of the fonds goes beyond the capacity of the workshop, the services of other technical experts or restoration workshops external to the Administration are contracted.

These measures apply to the documentary fonds that remain in deposit at the National Historical Archive. On the other hand, we have documentary fonds that are safeguarded by the institutions that generate them, as in the case of the municipal archives, the parish archives and the family archives.

The restoration section carries out the management of the preservation and restoration of these archival fonds, attends to their periodical control, follow-up and correct preservation (control files). In spite of this action, the preservation of these fonds depends, in the end, on the institutions or owners who safeguard them.

Although a substantial volume of documents is handled at the National Historical Archive, this volume lies within the capacity of the Archive, which allows it to carry out an individualized preservation and recovery plan.