The most important legislative function performed by ICAO is the formulation and adoption of Standards and Recommended Practices (SARPs) for international civil aviation.
What is the purpose of ICAO in regard to aviation?
The organization sets standards and regulations necessary for aviation safety, security, efficiency, and regularity, as well as for aviation environmental protection. ICAO also serves as a clearinghouse for cooperation and discussion on civil aviation issues among its 193 member-states.