Why do the NHS savings matter?
It is easy to be lulled into a false sense of security about NHS efficiency savings.
The doors to GP surgeries and hospitals remain open and, come what may, patients always seem to get treated - eventually.
In fact, the very term itself sounds rather innocuous.
But make no mistake: how the NHS fares in the next few years in achieving its £20bn target will go a long way to determining what sort of health service the country has in the future.
If it does not achieve what it needs to it will be patients who suffer.
The £20bn figure equates to a saving of about 4% a year until 2015. That is unprecedented for a health system.
If the NHS does not become more productive it will simply have to cut what it does to cope with the rising demand from factors such as the ageing population and obesity.
And what is worrying about the National Audit Office (NAO) report - despite the praise for the good progress that has been made to date - is that there are signs this could be starting to happen.
The watchdog found evidence of rationing in areas such as cataract surgery. The tactic, which involves making patients wait until their eyesight deteriorates further before they get treatment, makes a huge difference to an individual's quality of life.
As does the trend - noticed by orthopaedic surgeons - of leaving patients in pain for longer before they are entitled to hip or knee replacements.
Public Accounts Committee chairman Margaret Hodge - like many monitoring what is happening - is worried about what lies ahead.
Responding to the NAO report, she urged the Department of Health to be careful that the efficiency drive did not lead to the NHS "shutting the door" on patients.
But what makes the watchdog's findings even more startling is that despite the NAO calling it the first year of the savings, the health service has still had plenty of time to prepare for the savings drive.
NHS chief executive Sir David Nicholson first proposed the target three years ago and told the NHS to start looking for them in 2010-11 - the last year in which it got a significant increase in its budget.
That is why inside the health service the alarm bells are ringing loud and clear.