As demand grew, a new hospital with 150 beds, designed by architect Oswald Lewis, was built on its present site in Victoria Street, Darlinghurst, in 1870.

The first Australian heart transplant was performed on 23 October 1968 by a team led by Harry Windsor on a 57-year-old, Richard Pye, who survived for 45 days after the operation.

[7][8][9] The hospital was also one of the first health care facilities in Australia to begin treating AIDS patients when the epidemic reached Sydney in the early 1980s.

[10] This was a direct result of the hospital's close geographic position to the predominantly gay areas surrounding nearby Oxford Street and the injecting drug-using population of the notorious red-light district, Kings Cross.

[11][12][13] As the AIDS epidemic grew in Sydney, the hospital led the way in the compassionate treatment of the sick and the dying, continuing to apply the original values of the Sisters' mission.

This early exposure to the frightening implications of a possible pandemic was responsible for St Vincent's becoming one of the leading centers of immunology research and practice in the world.

The hospital was also one of the first health care facilities in Australia to suggest the idea of a needle exchange program, in an effort to stem the spread of the virus among IV drug users in the local community, an idea that was highly controversial at the time, and raised the possibility of criminal charges against doctors and other health care workers who implemented it.

[14][15] The immunology ward of the hospital was strongly supported by the local gay community, who staged numerous charity events to raise money for AIDS care.

Hospital management held discussions with leaders of HIV/AIDS groups in Sydney, explaining the reasons for the ward closure, and highlighting an increase in outpatient and ambulatory care services that would be provided instead.

The hospital is a primary teaching facility and offers a wide array of clinical experience to students studying medicine and nursing in particular.

[24][25] In line with the Sisters' original mission, the hospital oversees the largest population of homeless people in Australia (many of whom also have a mental illness), concentrated in the neighbouring suburbs of Kings Cross, Surry Hills, and Woolloomooloo.

[48] The NSW Government used a photograph of an infected patient from the ward as part of its campaign to urge the public to stay home in an attempt to curb the spread of the Delta variant.

[49] In 2016, a government-ordered review[50] found the hospital made “factual errors” and “key omissions” after it was revealed that 78 patients, including 30 who had died, were under-dosed with the chemotherapy drug carboplatin, finding the public was misled on the treatment.

[53] On 26 December 2021, SydPath (St Vincent's Pathology), admitted in a statement that more than 400 COVID-19 positive people were incorrectly notified that their PCR test results were negative on the previous night.