Anglo American, one of South Africa's biggest employers, announced on Tuesday that it would make anti-retroviral therapy available to staff that required it.
The firm reckons that almost one-quarter of its staff are HIV-positive, a far higher proportion than the 11% infection in the population as a whole.
"This sets a great example," said Hein van der Walt, director of employers' federation Cofesa.
"We're very pleased," said Vukani Mde, a spokesman for trade union group Cosatu.
"Awareness programmes are all very well, but someone had to take the initiative to do something."
Not your job
Campaigners and pundits were also buoyed by the Anglo American decision, reserving particular praise for the firm's willingness to reform the masculine culture of its mining operations.
The fact that many mine workers are separated from their families in all-male hostels has long been seen as a major contributor to the spread of HIV.
But most pointed out that Aids treatment should ultimately be the preserve of the government, which has remained defiantly sceptical about anti-retroviral treatment.
"This is not really the responsibility of the company," said Mr van der Walt.
"The government is in denial."
This may be starting to change: the day after the announcement, the African National Congress' parliamentary health study group publicly supported the use of anti-Aids drugs for the first time.
"This initiative illustrates the critical role that the business sector can play in forging partnerships with government," said committee chairman James Ngculu.
Ethical worries
Not everyone was convinced by all details of the firm's initiative.
South African newspaper Business Day pointed out that the programme tied staff even more securely into the firm.
"There is also the ethical question of what happens when workers receiving the anti-retroviral therapy free of charge lose their jobs or can no longer work and have to return to their homes, often far from Anglo's mines," it said.
And mining rival BHP Billiton, another big employer in southern Africa, questioned whether drug provision could be the answer.
"You don't approach the problem by throwing drugs at it," said chief executive Brian Gilbertson.
"You know it can't cure you - it simply extends the life and has to be administered in a carefully planned way."
Like some other big employers, BHP has resisted calls for blanket anti-retroviral provision, fearing that the costs of such expensive drugs could spiral out of control.
BHP has a rate of HIV infection roughly half of Anglo's because, it claims, it uses far fewer migrant workers.