Watershed moment for nurse numbers?
For years ministers have maintained nurse staffing levels are a decision for individual hospitals.
Technically speaking the guidance from the National Institute for Health and Care Excellence does not contradict that.
It says local trusts still have to make their own judgements.
But by highlighting the one nurse to eight patient ratio it has set down a marker.
Regardless of the careful wording, this threshold is bound to be interpreted as a line in the sand.
But why one to eight? In recent years this has become widely recognised as the acceptable minimum.
The RN4CAST consortium, a research group involving teams from 12 European countries, has found hospitals with less nurses during the daytime on general wards would see around 20 extra deaths a year more than better-staffed hospitals.
In fact, it was this work which led to the Safe Staffing Alliance, which includes the Royal College of Nursing, Unison and the Patients Association, to call for the ratio to be adopted as an absolute minimum last year.
Ministers eventually accepted there needed to be some central guidance on this in the autumn after weighing up the findings of the public inquiry in the Stafford Hospital scandal.
That report had suggested staffing needed looking at.
Of course, setting guidance for nurse numbers is not altogether new.
It is already accepted that in areas such as critical care ratios are essential.
But applying this to general wards is another matter - and could have major implications for overall nurse numbers.
Research by the National Nursing Research Unit last year found that half of hospitals are regularly running wards with fewer than one nurse to every eight patients.
How hospitals pay for this when budgets are being squeezed will be crucial.