Librarians seek out and evaluate appropriate information resources online. Knowledge of students and curriculum remains the foundation of good school library service regardless of the format of the information provided or the source. Worldwide computer networks make sharing resources easier than ever before. Libraries advertise their holdings to the world, offering to loan materials on a cooperative basis. Libraries which participate in such arrangements offer their patrons a wider variety of materials from which to choose.
Librarians can count on cooperative libraries to provide infrequently used materials.
Some cooperative library systems even designate certain facilities to specialize in particular subject areas, allowing other units to broaden or concentrate their own collections. The librarian must be well versed in the collection development policy of the cooperative to properly plan and select materials to complement those available through diverse means. In teaching students and teachers to be discriminating users of information the librarian must also teach ethical use of the materials retrieved. Copyright and plagiarism become significant issues when digital copies may be seamlessly integrated into student work. The librarian is often the only person in a building with any training in these legal issues.