In 1969 the North Atlantic Treaty Organization (NATO) established the Committee on Challenges of Modern Society (CCMS). From the outset, the subject of air pollution was one of the priority problems of concern to the CCMS. This committee initially organized a number of pilot studies, which evolved into a series of regularly-offered conferences, named NATO/CCMS International Technical Meeting (ITM) on Air Pollution Modelling and its Application. The organization and operation of these meetings was an activity supported by the NATO Committee on Science for Peace and Security (SPS), which replaced CCMS in 2007. Starting in 2013, the ITM series became independent of NATO support, and continues as a broadly international meeting of the highest scientific stature. 

• 1969-1974 Air Pollution Pilot Study (Pilot Country: United States of America)
• 1975-1979 Air Pollution Assessment Methodology and Modelling (Pilot Country: Germany)
• 1980-1984 Air Pollution Control strategies and Impact Modelling (Pilot Country: Germany)

Pilot Country - United States of America (R.A. McCormick, L.E. Niemeyer)

• Feb. 1971 Eindhoven, The Netherlands First Conference on Low Pollution Power Systems Development.
• July, 1971 Paris, France Second Meeting of the Expert Panel on Air Pollution Modelling

• Oct. 1972 Paris, France 3rd ITM
• May 1973 Oberursel, Federal Republic of Germany 4th ITM
• Jun. 1974 Roskilde, Denmark 5th ITM

Pilot Country - Germany (Erich Weber)

• Sept. 1975 Frankfurt, Federal Republic of Germany 6th ITM
• Sept. 1976 Airlie House, USA 7th ITM
• Sept. 1977 Louvain-la-Neuve, Belgium 8th ITM
• Aug. 1978 Toronto, Canada 9th ITM
• Oct. 1979 Rome, Italy 10th ITM

Pilot Country - Belgium (C. De Wispelaere)

• Nov. 1980 Amsterdam, The Netherlands 11th ITM
• Sept. 1981 Menlo Park, California, USA 12th ITM
• Sept. 1982 Ile des Embiez, France 13th ITM
• Sept. 1983 Copenhagen, Denmark 14th ITM
• Apr. 1985 St. Louis, Missouri, USA 15th ITM

Pilot Country - The Netherlands (H. van Dop)

• Apr. 1987 Lindau, Federal Republic of Germany 16th ITM
• Sept. 1988 Cambridge, United Kingdom 17th ITM
• May 1990 Vancouver, BC, Canada 18th ITM
• Sept. 1991 Ierapetra, Greece 19th ITM

Pilot Country - Denmark (Sven-Erik Gryning)

• Nov. 1993 Valencia, Spain 20th ITM
• Nov. 1995 Baltimore, Maryland, USA 21st ITM
• May 1997 Clermont-Ferrand, France 22nd ITM
• Sept. 1998 Varna, Bulgaria 23rd ITM
• May. 2000 Boulder, Colorado, USA 24th ITM

Pilot Country - Portugal (Carlos Borrego)

• Sept. 2001 Louvain-la-Neuve, Belgium 25th ITM
• May 2003 Istanbul, Turkey 26th ITM
• Oct. 2004 Banff, Canada 27th ITM
• May. 2006 Leipzig, Germany 28th ITM
• Sept. 2007 Aveiro, Portugal 29th ITM

Pilot Country - Canada (Douw Steyn)

• May 2009 San Francisco, California, USA 30th ITM
• Sept. 2010 Torino, Italy 31th ITM
• May 2012 Utrecht, The Netherlands 32nd ITM

• August 2013 Miami, USA, 33rd ITM.
• May 2015 Montpellier, France, 34th ITM.

Pilot Country - Belgium (Clemens Mensink)

• October 2016 Chania, Crete, Greece 35th ITM
• May 2018 Ottowa, Canada 36th ITM