The gray literature encompasses documentation generated by local, regional, national and international institutions of all types of fields and sectors. It differs from the others by offering original (often raw) and up-to-date data that make them very valuable and because it is not distributed or acquired through conventional sales channels.

Traditionally it was difficult to consult but since the arrival of the internet, in the 90's, it is much more accessible (more even than edited publications). Most of the reports, statistics, annuals, surveys, trends, nomeclators, indicators, censuses, research papers, working papers, opinions and studies that we keep in the closed access area are previous to the 21st century in paper.

Currently, as we indicated, the most recent data are almost always accessible through the network, but others, with a more detailed level of disaggregation, such as the Microdata of the INE, have a restricted access and can only be consulted through a controlled procedure. In our library, these data are available to the faculty and the research staff (PDI).  On the other hand, since 2017, PDI of our university can directly request, without our intermediation, the Eurostat Microdata to the European Statistics Office thanks to the fact that University of A Coruña was recognized by Eurostat a researcher entity (prerequisite to be able to do an individualized request).