Before the congresses started of there was preparatory meetings in Scheveningen Netherlands and in Zürich Switzerland.
WEI-IEO Congress Logbook
Number, year, location and country. Hosting times is the number of times the country has acted as host for the congress.
| Number | Year | Location | Country | Hosting times | |
|---|---|---|---|---|---|
| 1 | 1951 | Paris | France | FR | 1 |
| 2 | 1952 | Kobenhavn | Denmark | DK | 1 |
| 3 | 1953 | Bad Homburg | Germany | DE | 1 |
| 4 | 1954 | Napoli | Italy | IT | 1 |
| 5 | 1955 | Noordwijk | Netherlands | NL | 1 |
| 6 | 1956 | Wien | Austria | AT | 1 |
| 7 | 1957 | Saltsjöbaden | Sweden | SE | 1 |
| 8 | 1958 | Oostende | Belgium | BE | 1 |
| 9 | 1959 | Madrid | Spain | ES | 1 |
| 10 | 1960 | Bürgenstock | Switzerland | CH | 1 |
| 11 | 1961 | Aix-en-Provence | France | FR | 2 |
| 12 | 1962 | Helsinki | Finland | FI | 1 |
| 13 | 1963 | Wiesbaden | Germany | DE | 2 |
| 14 | 1964 | Marienlyst | Denmark | DK | 2 |
| 15 | 1965 | Capri | Italy | IT | 2 |
| 16 | 1966 | Amsterdam | Netherlands | NL | 2 |
| 17 | 1967 | Interlaken | Switzerland | CH | 2 |
| 18 | 1968 | Innsbruck | Austria | AT | 2 |
| 21 | 1971 | Malmö | Sweden | SE | 2 |
| 22 | 1972 | Estoril | Portugal | PT | 1 |
| 23 | 1973 | Liège | Belgium | BE | 2 |
| 24 | 1974 | Harrogate | United Kingdom | GB | 1 |
| 25 | 1975 | Helsinki | Finland | FI | 2 |
| 26 | 1976 | Salzburg | Austria | AT | 3 |
| 27 | 1977 | Capri | Italy | IT | 3 |
| 28 | 1978 | München | Germany | DE | 3 |
| 29 | 1979 | Amsterdam | Netherlands | NL | 3 |
| 30 | 1980 | Montreux | Switzerland | CH | 3 |
| 31 | 1981 | Madrid | Spain | ES | 3 |
| 32 | 1982 | Eastbourne | United Kingdom | GB | 2 |
| 33 | 1983 | Kobenhavn | Denmark | DK | 3 |
| 34 | 1984 | Monte Carlo | France | FR | 4 |
| 35 | 1985 | Istanbul | Türkiye | TR | 1 |
| 36 | 1986 | Sandefjord | Norway | NO | 1 |
| 37 | 1987 | Pörtschach | Austria | AT | 4 |
| 38 | 1988 | Saariselkä | Finland | FI | 3 |
| 39 | 1989 | Capri | Italy | IT | 4 |
| 40 | 1990 | Würzburg | Germany | DE | 4 |
| 41 | 1991 | Visby | Sweden | SE | 3 |
| 42 | 1992 | Bern | Switzerland | CH | 4 |
| 43 | 1993 | Edinburgh | United Kingdom | GB | 3 |
| 44 | 1994 | Sevilla | Spain | ES | 4 |
| 45 | 1995 | Dublin | Ireland | EI | 1 |
| 46 | 1996 | Estoril | Portugal | PT | 2 |
| 47 | 1997 | Oslo | Norway | NO | 2 |
| 48 | 1998 | Linz | Austria | AT | 5 |
| 49 | 1999 | Ioannina | United Kingdom | GR | 1 |
| 50 | 2000 | Maastricht | Netherlands | NL | 4 |
| 51 | 2001 | Istanbul | Türkiye | TR | 2 |
| 52 | 2002 | Budapest | Hungary | HU | 1 |
| 53 | 2003 | Cannes | France | FR | 5 |
| 54 | 2004 | York | United Kingdom | GB | 4 |
| 55 | 2005 | Camogli | Italy | IT | 5 |
| 56 | 2006 | Naantali | Finland | FI | 4 |
| 57 | 2007 | Seattle | United States | US | 1 |
| 58 | 2008 | Lausanne | Switzerland | CH | 5 |
| 59 | 2009 | Dresden | Germany | DE | 5 |
| 60 | 2010 | Dubrovnik | Croatia | HR | 1 |
| 61 | 2011 | Stockholm | Sweden | SE | 4 |
| 62 | 2012 | Bilbao | Spain | ES | 5 |
| 63 | 2013 | Newport | United Kingdom | GB | 5 |
| 64 | 2014 | Utrecht | Netherlands | NL | 5 |
| 65 | 2015 | Krakow | Poland | PL | 1 |
| 66 | 2016 | Dublin | Ireland | EI | 2 |
| 68 | 2018 | Belgrade | Serbia | RS | 1 |
| 69 | 2019 | Braga | Portugal | PT | 3 |
| 70 | 2022 | Milan | Italy | IT | 6 |
| 71 | 2023 | Berlin | Germany | DE | 6 |
| 72 | 2024 | Ghent | Belgium | BE | 3 |
| 19 | 1969 | Ajaccio, Corse | France | FR | 2 |
| 20 | 1970 | Arenal, Mallorca | Spain | ES | 2 |
| 67 | 2017 | Ajaccio, Corsica | France | FR | 6 |