It's a familiar scene to motorists: an obscene gesture, a rude word and in some circumstances a violent or even fatal confrontation. Every day, thousands of drivers experience some form of vehicle-related crime, which, the experts say, is almost always avoidable.
Now, with carjacking and road-rage attacks on the increase, the personal safety of Britain's 33.8 million licence-holders has never been more of an issue.
In response to growing demand from individuals and corporate clients, a leading driver-training school has launched the UK's first practical self-defence course for motorists.
In addition to expert advice on how to avoid becoming a victim, drivers are taught basic techniques of unarmed combat, as pioneered by the Israeli military, just in case all other attempts to stay out of trouble fail.
"Almost every day, there are stories in the media about people being attacked, robbed or even killed in road-rage or carjacking incidents," says Simon Johnston, the director of AcciDon't, the fleet driver training company, which plans to roll the course out across the UK in the coming months.
"The trouble is that car security is so good these days that the only way a thief can steal a car, or something from it, is to have the keys - and the easiest way to get them is from the owner, with violence.
"People are increasingly aware and worried about how aggressive the roads are, and we have been getting more and more requests for advice on how to avert any possible confrontations before they happen," Johnston says.
The AcciDon't course sees instructors from the self-defence experts Krav Maga Scotland working alongside personal security experts, teaching techniques used by law enforcement agencies.
"There were about 11,500 carjackings in Britain last year. Surveys reveal that nine out of 10 motorists have experienced some form of road rage in the past 12 months, while one-fifth of drivers feel so unsafe that they carry some form of weapon in their vehicle," says Simon Leila, the director of Krav Maga Scotland.
"When you consider that there have been more than 200 lorry hijackings in Britain since the start of the year, and that cab drivers are regular targets for robbery, and that even ordinary drivers are at risk from car thieves, there is a need for better education in crime prevention and protection."
This is a sentiment shared by the likes of Ally Bennett, an office temp and one of the students on the inaugural course last week. The 26-year-old secretary from North Yorkshire does a lot of driving to her different jobs, and has had a number of bad experiences over the years.
"I once had a man follow me from Gretna to Edinburgh, blowing kisses and trying to get me to pull over," she says. "He had seen me at a filling station and took a fancy to me. I was on my own and it was very frightening. On another occasion, I had somebody try to run me off the road because I had done something they didn't like."
However, after just a few hours of training, the art of sticking her fingers into the eyes of a potential rapist or disarming a knife-wielding attacker appeared to be almost second nature.
Johnston says: "Other courses teach people how to drive more carefully, but we have gone one step further to teach all aspects of car-related personal security." Simple tips such as not pulling up directly alongside another car at traffic lights - to avoid a confrontation about who moves off first - and always leaving room for an escape route may seem obvious, but they are rarely practised.
"Ninety-five per cent of vehicle incidents, collisions or security issues are avoidable," Callum Black, the chief instructor on the course, assures his students.
"All it takes is a little forethought and change of behaviour to become more proactive rather than reactive."
A glance around the car park at the venue outside Glasgow, and the experts could instantly tell the cars that belonged to single women, men, older couples or families - just by the range of belongings left in view inside the car.
"Professional bad guys do this all the time and can quickly identify who is a possible easy target," says Leila, 41, who was a member of the England karate squad from 1984 to 1986. He has been teaching personal security for 20 years.
"Very few people always back into a car-park space so they can get away quickly, or always lock their doors as soon as they get in. Most of us don't even notice who is loitering around our vehicle when we get into it. It is all down to awareness, anticipation and avoidance."