The Montreal Protocol was signed by 196 countries.  If all parties implemented all the agreements, the ozone layer of the planet, which was seriously injured in the 20th century, would have to recover by 2050.

The Montreal Protocol is a unique international agreements developed and adopted by the international community as a response to a critical situation with chlorofluorocarbons (CFCs) and other ozone-depleting substances. For example, these substances were actively used in aerosols, refrigeration systems and many other items.

There are 2 biggest facts why international community start to prepare international legal act in this subject: growth in size of the hole in the ozone layer = increasing dangerous ultraviolet radiation and growth of greenhouse gases, which were the main factors of global warming.
In order to stop the destruction of the ozone layer and, in parallel, reduce the emission of greenhouse gases into the atmosphere, the Montreal Protocol was appeared. Accordant to Montreal protocol, countries gradually reduced the production and use of these substances. Thereby, another step was taken to reduce the rate of increasing global temperature. The uniqueness of the Montreal Protocol is that all countries have joined it and have fulfilled all the requirements.
As the result of the actions taken, the ozone layer is decreased. The Secretariat of the Vienna Convention and the Montreal Protocol, based on data provided by countries, says that the annual consumption of ozone-depleting substances decreased from 1.3 million metric tons in 1986 to 9 thousand metric tons in 2017.

Belarusian way

As I am from Belarus I would like to tell you a short information about implementation of Montreal Protocol in Belarus.

The Republic of Belarus was among the first countries in Eastern Europe  which wad signed the Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol. In 2001, our country adopted the Law on the Protection of the Ozone Layer, as well as a number of other national legal acts regulating the use of ozone-depleting substances. These measures allowed Belarus to be the first in Eastern Europe country that stoped using chlorofluorocarbons, halons, carbon tetrachloride and methyl bromide. Belarus implements the strategy of phasing out hydrochlorofluorocarbons until 2020. In the same year, our country plans to ratify the Kigali Amendment, adopted by the international community in Rwanda in 2016.