A high school is employing sniffer dogs to check students for drugs in the aftermath of the tragic death of a King's College student.
Along with the sniffer dogs St Kentigern College has also hired security guards to search students at the door and they will be forced to blow into a breathalyser if suspected of drinking.
The heightened security measures follow the death of King's student David Gaynor who was sent home early from his school ball last weekend. He died several hours later.
In a letter to St Kentigern parents, head of college Steve Cole said the tough new measures being introduced were intended as a deterrent to any possible inappropriate behaviour at tonight's ball.
"I must stress that whilst this added security measure may seem extreme to some, it is our response to the tragic events of last weekend. Our intention is to ensure a safe and enjoyable occasion for all those attending."
Mr Cole said a professional drug detection agency with family ties to the school had been employed.
The company would have two dogs with a handler, two investigators and two uniformed security officers - in additional to the school's normal security personnel - at the ball.
There would also be a highly visible sign-written vehicle prominently positioned so guests were well aware as they arrived that drug dogs were present.
Students had also been warned in advance, along with the letter sent home to parents.
Mr Cole said the school has had a breathalyser available at its balls for many years and this year it would again be used if deemed necessary.
Anyone suspected of being intoxicated or in possession of drugs would be placed into a "time out" room - which is manned by both medical staff and senior school staff - and assessed. If found to be intoxicated or in possession of drugs their parents would be called to collect them immediately.
"Whilst we are saddened that we feel the need to introduce these measures, the support that you have shown us this week, along with that of the students we have consulted, confirms that this action has been viewed positively."
Secondary Principals' Association president Patrick Walsh said he was not aware of any other schools having used sniffer dogs before, although breathalysers had been commonplace for some time.
Asked if schools needed to be going to such extremes, he said: "I think, as the headmaster of St Kentigern said, it's a sad indictment on the way things are really and one would have to question the parents' role in all of this because they are the ones putting on the pre-ball functions. They have been asked not to by schools and yet they continue to do that.
"The pre-ball and after-ball are becoming the major features and the ball is just a distraction in between."
Mr Walsh said the problem affected schools across all deciles and was becoming so bad that many were now considering the future of school balls.