Once a city has lodged a bid with the BIE other cities will have six months to respond. The earliest allowed time to lodge a bid is 2011, and the latest is 2014.

As a Registered Exposition it must be six months in length and adhere to a wide universal theme that applies to all humanity.

Recent themes of Universal Expositions include "Man and His World" Montreal Expo 67, and "Discovery" Seville Expo 92.

The following cities have indicated an interest in hosting Expo 2020 ( see the poll)

c'est dommage qu'il n'y a aucune ville marocaine , qui veut organiser cette expo
"apart l'aventure de tanger 2012"