Belgium: Prince Phillip
Kuwait: Sheik Ahmad Al-Fahad Al-Sabah (IOC).
Liechtenstein: Princess Nora (IOC).
Luxembourg: Grand-Duke Henri (IOC) and Grand-Duchess Maria Teresa, with Prince Sébastien and Princess Alexandra attending the Opening.
Malaysia: Prince Tunku Imran (IOC)
Monaco: Prince Albert II (IOC). Charlene Wittstock might show up too.
Netherlands: Prince Willem-Alexander (IOC), and Princess Máxima (till Aug 17th).
Norway: King Harald and Queen Sonja. Crown Prince Haakon will replace them towards the end of the Games.
Qatar: Prince Tamim bin Hamad al-Thani (IOC)
Sweden: King Carl XVI Gustaf and Queen Silvia (from Aug. 14th).
UAE: Princess Haya bint Hussein.
United Kingdom: The Princess Royal, Princess Anne (IOC).
It is believed that ex-King Constantine of Greece will also be at the Olympics, due to him being an honorary IOC member.
The Olympics start this Friday, August 8th, so keep your eyes open for some royals!