Digital Library Service Integration (DLSI) aims to provide a systematic approach in integrating the services and collections of National Science and Digital Library. The National Science and Digital Library collections can share the services among themselves in a totally integrated environinent. Collections as such will require no change to plug into the DLSI architecture. Collections will keep using the services of NSDL in the similar manner as before. These services will in turn pass few parameters to the services of DLSI. With the help of these parameters, wrappers will fetch the details and priority of the users. These wrappers will be using the services of Search and Discovery module, Metadata Management services, and Access Management services. Users will see a totally integrated environment. They will see their digital library system just as before. In addition to that, they will find some extra link anchors on the document. These links serve to provide the supplemental information or arrange the information in the user preferred way. For this matter, the DLSI maintains basic user's information and preferences. Other contributions include incorporating collaborative filtering for customizing large sets of links, and advance lexical analysis tool to identify the objects of interest in a document.