- 2022 17-19 August 2022, Montréal, Canada (44th)
- 2021 27-29 October 2021, Barcelona, Spain (43nd)
- 2020 10-12 November 2020, Tokyo, Japan (42nd) CANCELLED DUE TO COVID-19 PANDEMIC
- 2019 10-12 July 2019, Washington D.C., The USA (41st)
- 2018 24-26 October 2018, Budapest, Hungary (40th)
- 2017 19-21 July 2017, Madrid, Spain (39th)
- 2016 20-22 July 2016, Seoul, Korea (38th)
- 2015 5-7 August 2015, Ankara, Turkey (37th)
- 2014 30 July - 1 August 2014, Turku, Finland (36th)
- 2013 7-10 August 2013, Rio de Janeiro, Brasil (35th)
- 2012 22-24 August, Tokyo, Japan (34th)
- 2011 31 July - 3 August, Oxford, United Kingdom (33rd)
- 2010 7-10 July, Paris, France (32nd)
- 2009 23-25 September, Lüneburg, Germany (31st)
- 2008 1-3 December, Sydney, Australia (30th)
- 2007 17-19 October, Washington DC, USA (29th)
- 2006 16-18 August, Copenhagen, Denmark (28th)
- 2005 2-4 November, Halifax, Canada (27th)
- 2004 27-29 October, Roma, Italy (26th)
- 2003 17-19 September, Brussels, Belgium (25th)
- 2002 16-18 October, Lisbon, Portugal (24th)
- 2001 3-5 October, Oslo, Norway (23rd)
- 2000 7-9 June, Belo Horizante, Brazil (22nd)
- 1999 6-8 October, Colchester, United Kingdom (21st)
- 1998 27-30 July, Montréal, Canada (20th)
- 1997 8-10 October, Stockholm, Sweden (19th)
- 1996 2-4 September, Vienna, Austria (18th)
- 1995 30 May - 2 June, Jarakranka, Poland (17th)
- 1994 August, Bielefeld, Germany (16th)
- 1993 Amsterdam, Netherlands (15th)
- 1992 16-18 June, Rome, Italy (14th)
- 1990 9-13 July, Madrid, Spain (13th)
- 1989 11-15 September, Varna, Bulgaria (12th)
- 1988 14-16 June, Budapest, Hungary (11th)
- 1986 18-19 August, New Delhi, India (10th)
- 1984 8-10 August, Espoo/ Helsinki, Finland (9th)
- 1982 Mexico City, Mexico (8th)
- 1980 1-3 October, Sofia, Bulgaria (7th)
- 1978 August, Uppsalla, Sweden (6th)
- 1975 October, Laxenburg, Austria (5th)
- 1974 August, Toronto, Canada (4th)
- 1973 October, East Berlin, East Germany (3rd)
- 1972 October, Brussels, Belgium (2nd)
- 1970 September, Varna, Bulgaria (1st)