The challenge
Plastic bags were a major and highly visible source of litter.
The case
In March 2002 Ireland introduced a 15-cent levy on plastic shopping bags, charged at the checkout and shown on receipts, with the money going to an environment fund. Use of plastic bags fell by over 90% almost immediately, from roughly 328 bags per person a year to around 21. The levy was later raised to keep usage from creeping back, and it inspired similar charges around the world.
Why it worked
A small, visible charge at the moment of choice changed a habit overnight. Showing it on the receipt and spending the money on the environment helped make it popular.
Sources
Spot an error or know a better source? Tell us