Fox News reported that the French publication Le Figaro spoke recently with Harrison Ford, who confirmed that preparations are underway for a fifth installment of the Indiana Jones franchise.
The story for the new Indiana Jones is in the process of taking form. Steven Spielberg, George Lucas and myself are agreed on what the fifth adventure will concern, and George is actively at work. If the script is good, I'll be very happy to put the costume on again.
No other details yet, although we know that Shia LaBeouf will return as Indy's son, Mutt.