Between the 1st and the 4h of July 2018, the 20th International Symi Symposium took place in Rhodes, Greece. Centered around George Papandreou, former Prime Minister of Greece and current President of the Socialist International and organized by the Andreas Papandreou Foundation, the symposium gathers every year leading intellectuals, politicians, Nobel laureates, entrepreneurs, diplomats, scientists, and activists to debate on current issues. Among the keynote speakers of this forum was Joseph Stiglitz, Nobel Prize in Economic Sciences. 

Joël Ruet intervened in a panel along with the former Bosnian Prime Minister Zlatko Lagumdzija, who is also a member of the Club de Madrid.