Legal Deposit

This is the main source of the National Library collection. The Government of India has enacted 'The Delivery of Books (Public Libraries) Act 1954', commonly called D.B. Act. Under the provision of this Act, all the publishers of the country, including the Government agencies have to deposit one copy each of their publications to the National Library and there by obtain a certificate of legal deposit. Newspapers and periodicals published in India are also to be deposited with the National Library, under the provision of this Act.

Purchase

Books and periodicals published out side the country and selected Indian publications are purchased to develop a comprehensive reading materials for the country. The purchase of books is centralised. Acquisition (Book Order) division is responsible to acquire the books through purchase.

Purchase policy: The selection of items follows the guidelines framed by the Reviewing Committee (1969) and the Committee of Management (1974), which are in turn based on the policy envisaged by Lord Curzon while opening the Imperial Library to the public. His policy was "the general idea of the whole Library is that it should contain all the books that have been written about India in popular tongue, with each additions as are required to make it a good all-round library of standard works of reference."

Gift Collections

Library receives books and other published materials through gift by individuals, institutions and libraries. One may donate any number of books to the library. Only those books which are not available in the library are generally accepted as gift.

Many noted scholars or their heirs have donated their complete collections. They are: Sir Asutosh Mukhopadhya, Jadunath Sarkar, S.N. Sen, Tej Bahadur Sapru, Munsi Sayyid Satruddin of Buhar, Imambara Zakaria, Sir Abdur Rahim, Hedayat Husain, Vaiyapuri Pillai, Ram Das Sen, Barid Baran Mukherjee. All of these collections are stacked separately under their names.

Exchange

The National Library has exchange relationship with 215 institutions in 90 countries. Through these institutions the library collects foreign publications, which generally, can not be acquired through normal trade channels.

Repository

United Nations Organization has recognized the National Library as the repository library for its and its agencies publications. The National Library receives all the publications of U.N.O., its agencies and from a few Governments of other countries.