To improve air quality on local, national and regional levels, ECE Member States have been working successfully to gradually reduce and prevent air pollution in the region. One of the vehicles through which this has been achieved is the Convention on Long-range Transboundary Air Pollution, which was signed in 1979. Over the years, it has been extended by eight protocols that identify specific measures to be taken by Parties to cut their emissions of air pollutants. The Convention has 51 ECE Parties. ECE Member States also formulate air pollution policies in the framework of the Committee on Environmental Policy.