The National Research Council (CNR) Bologna Research Area Library is a multidisciplinary scientific library serving a community of about 1.500 local and remote users among researchers staff, PhD, undergraduate students and visiting scientists. The Library became operative in 1997, progressively integrating the existing resources of the Institutes belonging to the Research Area thus reducing costs whilst increasing the quantity and quality of advanced library services, such as: access to over 6.000 online journals, access to specialised bibliographical databases, document delivery, etc... Library online collections cover, among the Earth Sciences, the fields of Geology, Ocenography, Climatology, Atmospheric and Environmental Sciences. Among library services, the Document Delivery Service allows rapid supply of scientific documents, books, theses and other documents not owned by the Library through Inter-Library loan and exchange or purchase. This service is for internal users. On the other side, the Library offers rapid and comprehensive document supply and interlibrary loan to other Italian libraries from its extensive collection. Document Delivery (DD) plays an important role in Italian research and university libraries. The main Internet resources for Document Delivery and Resource Sharing are the Archivio Collettivo Nazionale dei Periodici (ACNP, the collective serials Italian catalogue), the Sistema Bibliotecario Nazionale Catalogue (SBN) and the MetaOpac Azalai Italiano (MAI). In 1999 the Library started a project aiming at the development of an Internet-based Document Delivery Service, in order to: - exploit the new Internet technologies; - promote cooperation among CNR and Italian university libraries; - reduce service costs; - achieve short turnaround times and higher user satisfaction. The resulting system, NILDE (Network Inter-Library Document Exchange), is a web based software for libraries and end-users, that allows libraries to manage the entire work-flow of document delivery activities. The main advantages for libraries are the provision of synthetic and analytical statistics, provision of performance indicators such as “fill-rate” and “turn-around time”, and support for secure electronic delivery via Internet by means of a file-uploading/web-server. The main advantages for end-users are the possibility to forward a document delivery request to their library from any OpenURL-compliant bibliographical database (e.g. Web of Science, Scopus, Scifinder, PubMed, CSA Illumina and SFX platforms) and to check the status of their requests. NILDE is presently used by more than 500 Italian libraries and counts about 3.000 registered end-users. It has allowed to build up a large library network, based on cooperation, resource sharing and a degree of standard quality of service and fair behaviours. Technical-scientific and bio-medical libraries represent the core of the NILDE network, performing more than 80% of the total number of document exchanges. The most recent progress and implementation of the NILDE project and software will be presented. We will also focus on the important contribution made by earth-science libraries to the NILDE network and how it will be possible to increase it, by actively involving even more libraries and complying with the user-needs of earth-scientists.