Improving the environmental performance of aviation is a challenge ICAO takes very seriously. In 2004, the 35th Session of the ICAO Assembly adopted three major environmental goals, which have been reaffirmed in all subsequent Assembly Sessions:
a. to limit or reduce the number of people affected by significant aircraft noise;
b. to limit or reduce the impact of aviation emissions on local air quality; and
c. to limit or reduce the impact of aviation greenhouse gas emissions on the global climate.
ICAO policies and practices related to environmental protection are revised and updated every three years by the ICAO Assembly. Currently, these policies and practices are included in Assembly Resolutions A40-17, A40-18 and A40-19, adopted in October 2019.