As the premier reference and research library of Singapore, the National Library has two missions: To be a repository of the nation’s documentary heritage and support the information and learning needs of the nation. The National Library aspires to enable Singaporeans to understand all aspects of Singapore and its place in the world.

The National Library’s collection is broadly classified into the National Collection and the General Reference Collection, which are created and maintained for different purposes.

The National Collection encompasses the nation’s documentary heritage, which captures the diverse experiences of living in Singapore; as well as collections that document Southeast Asia and Singapore’s links with the region. The collection contains materials with content related to Singapore. They could include translated works, works by any authors or publishers, in all languages, at any audience levels and editions. Works published in Singapore are also collected as part of the nation’s publishing history. 

The National Collection serves to:

1. Preserve and promote the nation's heritage, arts and culture;
2. Document the publishing and intellectual output of Singapore and Singaporeans;
3. Enhance knowledge and understanding of Singapore's significance in the region and its place amongst neighbouring countries. These are Southeast Asian or other nations that are closely linked with or have direct social, cultural, economic and political impact on Singapore and its people.

Based on the National Library Board’s legislative responsibilities, the National Library aims to collect comprehensively through Legal Deposit, donations, gifts and materials exchange with other libraries and digital acquisition, in Singapore’s four official languages, namely English, Malay, Chinese and Tamil; and representatively or selectively in other languages, on or related to Singapore.

These include:

• Published or unpublished works on or about Singapore, produced in or outside of Singapore;
• Published works, in physical or digital format, produced locally by Singaporeans, or published by local institutions and organisations;
• Websites in the dot.sg domain registered with the Singapore Network Information Centre, and selected websites about Singapore;
• Works on Southeast Asia or the Association of Southeast Asian Nations (ASEAN) as an entity especially if these materials contain references to Singapore;
• Works on or about Malaya/Malaysia or written by Malayans/Malaysians, published in 1965, and earlier.

The National Collection will be preserved for future generations. The quality, depth and size of its Singapore or Singapore-related collection is what positions the National Library as the nation’s custodian of its documentary heritage. Acquisitions are balanced with considerations of the cost of accessioning, maintaining, preserving and providing access to the collection.

The National Library Board complies with the regulations and directives from the Ministry of Communications and Information and the Infocomm Media Development Authority of Singapore.

The General Reference Collection at the National Library supports the nation’s aspirations, reference and research needs. The National Library selectively collects the various fields under the Arts (from literary, visual to performing arts), Business, Social Sciences and Humanities, Science and Technology, as well as the Asian Children’s Literature Collection. The collection aims to offer a range of ideas and opinions.

The National Library acquires or provides access to core titles in the various fields as well as a selection of quality global publishing output to support research needs. The geographical coverage for the collections is wide. However, focus will remain on Southeast Asia and Asian materials, as Singapore’s cultural, political and business interests are closely linked to these regions.

Materials selected will be in the four official languages of Singapore: English, Malay, Chinese and Tamil, and materials are reviewed periodically for their currency to meet user needs.