State Library of South Australia

The State Library of South Australia, or SLSA, formerly known as the Public Library of South Australia, located on North Terrace, Adelaide, is the official library of the Australian state of South Australia. It is the largest public research library in the state, with a collection focus on South Australian information, being the repository of all printed and audiovisual material published in the state, as required by legal deposit legislation. SLSA's holdings include rare books, maps, manuscripts, and ephemera. It holds the "South Australiana" collection, which documents South Australia from pre-European settlement to the present day, as well as general reference material in a wide range of formats, including digital, film, sound and video recordings, photographs, and microfiche.

As of October 2025^[update], the director of the library is Megan Berghuis, who was appointed in 2024, after the retirement of Geoff Strempel.

The library collection was based on a number of forerunning societies and subscription libraries, until the South Australian Institute was incorporated in 1855, and a new building opened in 1861 to house the Institute's collection of books. The Institute Building opened in 1861. The Institute became a statutory body named the Public Library, Museum and Art Gallery in 1884, the year that the first purpose-built library building opened – now the Mortlock Chamber, designed by colonial architect E. J. Woods. In 1967 the Bastyan Wing was opened behind the Institute building, and finally in 2003, the glass-foyered Spence Wing, which connected the Bastyan Wing to the Mortlock Wing. The Institute Building and the Mortlock Wing have been state-heritage listed. In August 2025, the library was ranked second in a global literary tourism initiative called "1000 Libraries".

On 29 August 1834, a couple of weeks after the passing of the South Australia Act 1834 by the British parliament, a London-based group led by the Colonial Secretary, Robert Gouger, and solicitor Richard Hanson and a number of prominent colonists, including Ernest Giles, Edward Gibbon Wakefield, John Morphett, Robert Torrens Snr, and John Hindmarsh, formed the South Australian Literary Association at the city's Adelphi Chambers. Within a month, the title was changed to the more inclusive South Australian Literary and Scientific Association. This change aimed for "the cultivation and diffusion of useful knowledge throughout the colony". Although the Association lapsed and meetings ceased, a collection of books had been donated by members with the intention of becoming the basis of the new colony's library, and the colonists subsequently brought the collection to the Colony of South Australia aboard the Tam O'Shanter which arrived on 18 December 1836.

The first Adelaide Mechanics' Institute (based on the concept of mechanics' institutes developed in Scotland and England in the 1820s, to provide adult education to working men) met on 23 June 1838, with the event reported by the Southern Australian newspaper. Running into difficulties, the organisation was merged with a revived Literary and Scientific Association, with the new name of the Adelaide Literary and Scientific Association and Mechanics' Institute, electing a committee in July 1839. Over this time, the membership of the association varied between upper-middle-class and lower-middle-class. The library reopened, but the Institute did not have a permanent location, and the focus was on a programme of lectures. However the lectures dwindled and attendances varied, as the Institute tried to function as an adult education institution as well as a learned scientific society, and its last meeting was held in June 1844.

In September 1844, a group of men founded the South Australian Subscription Library, with a collection created by donation and subscriptions, and in 1845 it took over the collection of the Literary and Scientific Association and Mechanics' Institute. A permanent librarian was employed at this time, and the library served its middle-class members.

In 1847, a new Adelaide Mechanics' Institute was founded, by a group of lower-middle class men, led by schoolteacher W. A. Cawthorne. Various talks, discussions and displays were put on. This organisation merged with the South Australian Library in 1848, creating the Mechanics' Institute and South Australian Library, based in Peacock's Buildings, Hindley Street, and with membership moving back to the upper-middle class. Nathaniel Summers was appointed as the first librarian. It subsequently moved to Exchange Chambers, King William Street, but by 1855 had gone into decline.

Meanwhile, other institutes and societies were established throughout the Adelaide suburbs, including the Adelaide Philosophical Society (which later evolved into the Royal Society of South Australia). Some of these institutes asked the government for financial assistance, and Unitarian publisher John Howard Clark suggested the conversion of the Institute into a public institution. A Bill was proposed in Parliament in 1854. Between 1847 and 1856 another 13 mechanics' institutes started in other parts of the colony.