The methods, of receiving requests, processing the requests and mode of delivery of fax, electronic-mail or online systems. Documents may also be supplied by any one of the above methods. Of the above methods, online request and delivery of the document is the fastest, though delivery of documents in this mode is expensive. However, the speed of supply of documents depends on many other factors such, as time taken to locate the document from within the institution and if not available, then, time taken to find its location, transmitting the request, processing of the request by the library supplying the document, receipt of the document by the requesting library and finally delivering the document to the user. All these factors affect the speed of supply. It may range from within a day to a few months. If service is operated from a centralised collection, then, the delivery is quick ranging from, say, two hours to two days. With the availability of online databases, online public access catalogues, etc., it is possible to search for information from remote locations on the networks, request the selected document and receive the required document electronically almost instantly. Electronic document delivery systems offer a great promise. Here, speed is the major attraction. However, copyright issues and high cost are some of the constraints which are attracting the worldwide attention.