Presents a project developed for the teams of the Library and the Conservation-Restauration Laboratory of the Museum of Astronomy and Sciences(MAST), with the objective to establish a Policie of Preservation for Special Collections. Describes as this interaction, allied the auto-instruction by means of specialized literature, facilitated the evaluations made by the library. Considers the planning of preservation in the scope of the librarian management. Ciscusses some reached results already in the treatment of these collections, throughout more than ten years, and the actions that are in progress. It reflects concerning the importance of the librarian custodian of Special Collections in acquiring the knowledge referring technician to the preservation area, in order to propitiate ways for management it quantity under its safekeeping.