The Montreal Protocol adopted

The Montreal Protocol on Substances that Deplete the Ozone Layer was adopted.  The protocol is designed to protect the ozone layer by phasing out the production of a number of substances believed to be responsible for ozone depletion.

The protocol was later either adjusted and/or amended in

London 1990
Copenhagen 1992
Vienna 1995
Montreal 1997
Beijing 1999

The protocol has been ratified by over 190 states.

The UN Environmental Programme's website on Ozone

_{Credit: UN Photo/Yutaka Nagata|}

_{Noel J. Brown (third from left), Director of the New York Liaison Office, United Nations Environment Programme (UNEP), speaking at a forum on "Critical Environmental Issues: Ozone Depletion" organized by UNEP.  Also seated at podium from left to right are: Michael Oppenheimer, Senior Scientist of the Environmental Defense Fund; Stephen R. Seidel, Senior Analyst, US Environmental Protection Agency; and Russell M. Sasnet, Senior Executive, General Electric Co.}