The Montreal Protocol on Substances that Deplete the Ozone layer was signed on September 16, 1987. It was a protocol to the Vienna Convention for the Protection of the Ozone Layer. It was an international treaty signed by 20 countries, aiming to stop the production of substances that cause depletion of the ozone layer, including Chloroflurocarbons (CFCs).

This treaty has been deemed a great success as current estimates indicate that the ozone will return to 1980 levels in the next 20 to 50 years.