The advent of computerized information systems hasn't really changed the librarian's role described above; but it has surely changed the format of the materials we select, whether or not we collect them, and how we maintain our links to this information. Computers in libraries have also changed the methods we use to retrieve information, and the kind and amount of instruction we must provide our users.
This paper will examine how, in a very short time, the World Wide Web has revolutionized astronomy libraries, and will continue to do so as the electronic versions of our traditional books and journals become more widely available and more accepted by library users.