Categories of Document Delivery Services 

There tare different agencies concerned with document delivery service. Let us try to some of these agencies and the way they function enabling the end-user to receive the document required by him/her in an appropriate form and format. Some of the services are discussed in the following paragraphs. 

1. Library networks and consortia, including national libraries and document delivery services. The central focus of these networks being resource sharing and the creation of shared bibliographic and catalogue databases. Such agencies may also offer a range of other value-added services such as online search services. 
2. Document delivery on CD-ROM, which is particularly appropriate in the context of books, encyclopaedias and other lengthy documents. 
3. Commercial Document Delivery Services, which operate with alliances with online search services and draw on the resources of a number of other libraries. 
4. Library suppliers and Serials supplier agents, who have used networks and EDI, (Electronic Data interchange) to improve the document ordering process and associated processes such as altering invoicing and book processing. 
5. Electronic journal publishers and suppliers. It may be noted that there is a limited number of e-journals at present, but significant efforts are being made in the digitization of journals that have been previously distributed in the printed form. This effort would certainly enhance the electronic document delivery service efforts. 

Some important aspects relating to the above mentioned categories of document delivery services need to be understood properly. For example, library networks and consortia usually create catalogue databases as a means of accessing and sharing the resources of a group of libraries. Though, any type of document could be exchanged, the main emphasis is on printed documents. Similarly CD-ROM suppliers of full text and multimedia databases, would be more helpful as document delivery service vendor's only for the supply of bulky documents such as encyclopaedias, etc., their services may be availed only when such documents are to be delivered for. 

It must also be noted that document delivery services, including commercial ones, and institutions such as British Library may provide ,access to documents announced through the database available from online services. But the emphasis would be on journal articles; conference papers, etc., along with books. 

In conclusion is may be stated that document delivery service is one of the important aspects of information dissemination. This service will continue to be delivered in a range of different electronic as well as print formats for years to come. Different formats are appropriate for different purposes. In the years to come, there may be changes in the means of access to document and the agencies involved in providing that access.