It rapidly outgrew its space and ran into financial difficulties that were alleviated in the early 21st century under new director Elizabeth Ann Macgregor, who eliminated regular admission fees and diversified the museum's funding sources.

After two proposed expansions failed, a design by local architect Sam Marshall met with sufficient approval to raise money for its construction.

To the west and northwest, the Rocks is urban and densely developed up to the bridge's southern approach, with attached two- and three-storey mixed-use buildings from the 19th and early 20th centuries.

[7] On the central clock tower, the main entrance is a recessed pair of dark bronze doors topped by a sandstone frieze depicting sailors and dockworkers.

[10] Above the entrance, the clock tower treatment consists of three more widely separated but otherwise similar windows rising from the third storey to the sixth and topped with a decorative pink granite facade depicting a propeller, wheel, and anchor.

[14] When used by the Maritime Services Board the interior made extensive use of scagliola and terrazzo to imitate marble flooring and walls, a common technique at the time.

[6] One, William Henry Withers, designed a Stripped Classical building for the agency, with a central tower meant to echo the pylons of the nearby bridge.

[23]: 17  After site clearance construction was halted in late 1940 since restrictions resulting from the onset of World War II made continued work impossible.

It was to be used specifically for "museums and other places for the purpose ... of suitably housing the works purchased so as to bring the people of Australia in more direct touch with the latest art developments in other countries.

[29] After the relocation of the Maritime Services Board (MSB) to larger premises in 1989, the building and site were donated by the Government of New South Wales to the Museum of Contemporary Art.

[35] The Japanese architectural studio SANAA won, but its plans were abandoned after site investigations revealed the archaeological remains of a colonial dockyard beneath the museum's car park.

[1] In 1999, with the MCA facing the prospect of bankruptcy,[36] having just enough money to make payroll for a few weeks,[34]: 08:10  the board hired Elizabeth Ann Macgregor, a Scot who had worked with the Arts Council of Great Britain, as director.

[37] Macgregor had previously held the same post at the Ikon Gallery, a major contemporary art museum also housed in a repurposed heritage-listed building in Birmingham.

[34]: 16:50–17:50 Macgregor also began requiring that curators consult with less artistically inclined peers about the text in wall labels identifying and describing the adjacent works.

"[36] After fending off a 2000 effort by the Art Gallery of New South Wales to annex the MCA,[37] Macgregor began developing plans in 2002 for an extension to the museum.

"The elevators were well past their natural life, the stair circulation was not appropriate and there was no infrastructure to deal with disabled people", recalled Simon Mordant, a Sydney investment banker who later chaired the MCA board.

They were built to a design by Sydney architect Sam Marshall, taking two forms: infill on the building's west facade, allowing shop space on the ground floor facing George Street, and the new Mordant Wing on the north.

Elizabeth Farrelly, generally cool to the wing[a] in a March 2012 Sydney Morning Herald opinion piece, called that connection "undeniably the new building's triumphant spatial moment.

"[43] Artist Profile, much more enthusiastic about the addition, which it said "successfully fuses the old with the new by forging innovative ways through which audiences can interact with and understand the work on offer", used similar language.

Tickets to it sold out regularly over the nearly four months it was at the MCA; the museum extended its hours and offered special "unplugged" nights where selfies were forbidden to accommodate the crowds.

Macgregor credited the coincidence of an exhibit by an artist whose work celebrates the female body opening just as the #MeToo movement began trending worldwide.

In July 2020, Lorraine Tarabay, another investment banker[49] and contemporary art collector, took over the chair of the board from Mordant,[50] who remains involved with the museum as its international ambassador.

[59] Director Macgregor made up for the loss of revenue from the abolition of the regular entrance fee at the beginning of her tenure with increased monetization of the museum's book and gift shops.

The donation boxes at the entrances also captured additional funding from patrons, and after the 2010 renovations the cafés and rent from the spaces inside the museum ($4 million, according to Macgregor.

[34]: 28:50 ) and shops and other tenants on George Street, including the 600-square-metre (6,500 sq ft)[60] main offices of the Australian Olympic Committee,[61] further supplemented the museum's self-generated income.

[48]: 59  Another 24 per cent was from private and corporate donors; the rest came from its various other sources of revenue,[36] such as spending at the shops, admission fees to special exhibitions and earned interest.

[67] Four years later, to coincide with the Sydney Olympics, it was displayed in the entrance galleries in the exhibition Yolnu Science: Objects and Representations from Ramingining, Arnhem Land,[67] curated by Djon Mundine and Linda Michael.

[75] Two works by John Mawurndjul, Nawarramulmul (Shooting Star Spirit, 1988) and Ngalyod (Female Rainbow Serpent, 1988), were the first artworks acquired for the dedicated MCA collection in 1989.

[85] The National is a series of biennial survey exhibitions featuring contemporary artists, run as a partnership between the Art Gallery of New South Wales, Carriageworks and the MCA and held across the three venues.

[91] The caravan, designed by artists Bruce Odland and Michael Luck Schneider,[92] is fitted with technical devices that create sensory responses to sights, sounds and vibrations.