More than a decade ago, the Swedish government approved a revolutionary safety idea. Deciding that zero road deaths was actually a realistic goal, the parliament in Sweden approved a set of four principles related to traffic and road safety.

At the core of Vision Zero, which has since spread to other countries including the Netherlands, Norway, and the UK and to U.S. cities including San Francisco, New York, Boston, and Portland, is the idea that roads and traffic patterns should be designed to lessen the negative effects of traffic collisions. In addition, speeds of moving vehicles should be adjusted, where possible, to cause the fewest deaths.

For example, it is known from studies that at 25 mph about half of pedestrians hit by cars will die; lower the speed to 19 mph and very few of the crashes will result in fatalities. Considering that 1.3 million people die each year in vehicle crashes, Vision Zero is a very laudable goal for a country to take.

Of course, reducing vehicle speeds is not always that popular and it certainly isn’t very sexy. Humans like to go fast.

The Danish police, in their effort to calm traffic and reduce injury accidents, recently came out with a public service announcement that perfectly, and quite sweetly, sums up why having a ‘Vision Zero’, and putting in place the type of aggravating mechanisms that make us slow down, is a necessary inconvenience.

In the ad below, a Danish man is shown zipping along a road in his (Swedish) Volvo. You get the sense he might be speeding. Juxtaposed are frames of a young girl getting ready to take a bike ride.

As he barrels ahead, and the girls straps her Nutcase helmet in place, and the viewer has a quick second of foreboding. But then the driving man passes a speed-checking ‘photo wagon’.

You know immediately that the man was speeding, was photographed speeding, and will probably soon be receiving a hefty speeding ticket in the mail. His swear word, while in Danish, is immediately recognizable – nearly any viewer can empathize with the feeling he’s having.

But then the camera shows his car pulling into the garage where the young girl has hopped on her bike. She bangs a hand on the hood of the man’s Volvo and smiles to the driver, now revealed to be her dad as she calls out, “See you later, father,” before she begins to wheel away.

And that’s all you need to know – the ad ends with the tag line “More photo wagons, lower speeds, fewer collisions,” as the girl rides off down the road.

The message is pretty clear. Protecting the most vulnerable users of the road – the walkers, the strollers, the bike riders, the skateboarders – justifies the irritating photo wagons, speed cameras, and other forms of getting us to collectively slow down.