Pubs outside Dublin, or at least those that don't usually serve food, reopen today after a six-month lockdown.
Some pubs may not reopen for various reasons but those who do, and those who visit them today, carry an enormous responsibility.
That responsibility stretches across publicans, their customers, their staff, and society in general.
The great majority of pubs and their customers will willingly observe, in deed and in spirit, the unavoidable pandemic restrictions.
Inevitably and unfortunately, there will be a minority who do not.
The size of that minority is of huge significance as is the majority's ongoing commitment to public health measures.
If that minority is significant and can be linked to new C19 infections then the pubs will inevitably be closed again.
Should that transpire it is hard to imagine a new opening date until after Christmas.
That would have a devastating impact on a sector already struggling with a once-in-a-lifetime income collapse.
It would also extend to almost a year the period of relative isolation facing many people who rely on pubs as a social hub.
It would also consolidate the kind of social and personal changes that may change our pub culture for ever.
Today's reopening is important on many, many levels but if it is to be a success rather than an unsustainable promise then that old public health warning - Drink Responsibly - must take on a new extended meaning.