In Kenya, you take your life in your hands when you travel between towns in a matatu – a small bus or minivan. They are notoriously driven fast and furiously, contributing to one of the highest road death rates in the world.

The Kenyan government tried a number of expensive options, including:

  • lowering speed limits
  • repairing damaged roads
  • encouraging the use of seat belts
  • installing speed bumps
  • cracking down on drunk-driving

Then two economists came up with an ingenious solution.

James Habyarimana and William Jack recruited 2,276 matatu drivers. James and William affixed stickers in the vehicles whose license plate ended with an odd number. Vehicles with a license plate ending with an even number were the control group.


Example stickers. Other stickers included gruesome images as well as text.

All the stickers urged passengers to take action, by complaining about dangerous driving and asking the driver to slow down.

One year later, the researchers found that passengers in vehicles bearing stickers were three times more likely to speak up.

Total insurance claims from vehicles with stickers fell by nearly two-thirds, and claims for accidents involving death or serious injury fell by over 50%. Drivers admitted that it was passenger complaints that caused this change in their behaviour.

Adding call-to-action stickers saved more money and more lives than anything else the Kenyan government had tried.

If you don’t ask you don’t get

As I have said before, when you tell people what you want them to do, they are more likely to do it, as long as you make it easy for them.

All marketing has an objective. Your objective is your most wanted response. Turn that into your call to action.

With that in mind, please add a comment below and share this article with your network. Thank you.

This case study is adapted from a story in Daniel Pink’s book To sell is human.






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