On the last Friday before Christmas, revellers across the UK pile out of their offices ready to celebrate with a few (or a few too many) drinks.
The day has become so notorious, some people have given it a nickname: Mad Friday or, in places, Black Eye Friday.
It is one of the NHS's busiest days of the year for treating alcohol-related illness and injury.
That's why one charity is calling for Black Eye Friday to be given a new nickname.
Maxine Thompson-Curl, chief executive officer of One Punch UK - a charity which raises awareness of one-punch assaults and killings - says the name glorifies violence.
Ms Thompson-Curl set up the charity after her son was killed in 2011 from a one-punch assault.
"The name of it is giving people the go ahead just to be violent," she said.
"We want to call it Festive Friday, because it's about having fun."
My husband was killed by one punch at Christmas
Caroline McGuiness's husband Ian Allan was killed after he was punched on the weekend before Christmas in 2001.
Ian, then 34, was on a night out with friends in Newcastle when an argument broke out in a taxi queue.
As the argument petered out, one of the group punched Ian in the head. He fell backwards, hitting his head on the pavement.
It was 11:30pm when Caroline, who was 16 weeks pregnant, got a call from a police officer saying Ian was in the local A&E department.
"I was expecting him to be there with a bloody nose and looking a bit sheepish," she recalls.
But he had swelling on the brain and had to be kept in a medically-induced coma over the whole of the Christmas period.
Caroline, helped by her sister, had to put on a brave face for their three-year-old daughter.
"We moved the Christmas tree through to the dining room, but we still had to have a Christmas for her," she says.
She recalls driving back home from the hospital one night when Mariah Carey's All I Want For Christmas Is You came on the radio.
"That's all I wanted - him," she says.
On 28 December, six days after the initial assault, Ian died from complications from pneumonia.
Karl Layton, then 24, admitted manslaughter. He was sentenced to 15 months in prison.
Caroline says she supports One Punch UK's campaign to rename Black Eye Friday.
"[The name] just makes me sick. It gives me a nauseated feeling in my stomach.
"Do people think that it makes it all right to punch people because that's the name of the day?"
Caroline says she's since tried to compensate for what her family have lost at Christmas, but still looks back to that day.
"I had to bring a new daughter in the world. My daughter doesn't have an absent father - he's dead."
Ms Thompson-Curl believes the Black Eye Friday name may be regional - with people often using it in north-east England.
According to Google Trends, Northern Ireland has the highest proportion of searches for Black Eye Friday across the UK, followed by England.
NHS England has said it is making up to £300,000 available over the festive period to fund dozens of so-called drunk tanks, where inebriated revellers can be checked and allowed to sleep it off.
Black eye Friday is cancelled!— PSNI M&EA District (@PSNIMEADistrict) December 21, 2018
It’s 2019 and the season of goodwill to your fellow Man
One Punch can kill, DONT wake up tomorrow with a hangover that stays with you for life
Please Enjoy Festive Friday responsibly & stay safe
Con B - NPT#KeepingPeopleSafe #Police #PSNI pic.twitter.com/zQcJcT6Mji