Internet provides the powerful telnet function which allows users to login remote hosts and systems. More and more libraries, especially academic libraries, mounted their online public access catalog (OPAC) systems under Internet and permitted users to login their systems through internet. Stanford University Library Catalog -- SOCRATES is a very excellent OPAC system in the world. It has changed the traditional OPAC into a new type of information system. Libraries have a responsibility to provide every feasible means of information for their patrons. With application of network technology, libraries face many challenges to adjust their services for accommodating the network environment. What kind of problems we will meet and how can we employ the full potential of the network are discussed in this artical. As libraries entering the period of network, we should rethink our traditional missions including both technical and public aspects for exploiting the network technology to promote our services.