By definition, the Archive is the institution that preserves, organizes, manages and disseminates documents and documentary collections. It is a service, therefore, dedicated to the custody, management and dissemination of documents generated by people, companies, entities, administrations and public or private institutions, throughout their existence and in the exercise of their own functions .

The Archive has a cultural function as a resource for the knowledge of the history of the city and the region. It organizes dissemination activities, such as exhibitions or conferences, makes publications, collaborates with other institutions or entities, etc.

In Reus, the same space houses two archives: the Baix Camp County Archive and the Reus Municipal Archive.

L'Municipal Archive of Reus has the funds generated or received by the Reus City Council. Today it basically has an administrative function, that is to say, to facilitate and speed up the resolution of administrative procedures and enable access to information by citizens, in accordance with current legislation. Also, in the field of dissemination, in addition to the aspects already indicated, it advises citizens on issues of history or genealogy, among others.
The facility is a new building with a capacity to install around 16.000 linear meters of documentation, distributed over four levels. The facility also has a library, a newspaper library and a multipurpose room with a capacity for around fifty people.