Prince Albert of Monaco, a member of the International Olympics Committee, has been a regular fixture at various events.
The royal, who used to compete in bobsleigh at the Winter Olympics, watched the men's basketball match between Spain and Brazil.
Happy snapper Albert didn't miss the opportunity to take a few selfies during the game.
Princess Anne rubbed shoulders with Prince Albert, as the pair took in the swimming finals on day two of the Olympics.
The Queen's daughter will have been particularly proud to see Team GB's Adam Peaty score Great Britain's first gold medal, completing the 100m breaststroke in 57.13 seconds.
Another member of the IOC, Crown Prince Frederik of Denmark has been a fervent supporter of the Games and flew to Brazil with his wife Princess Mary days before Rio kicked off.
He had pride of place at the opening ceremony on Friday 5 August, where he cheered on Denmark's national team as they paraded out.
The couple were all smiles as they watched the ceremony at the Maracana stadium.
King Philippe and Queen Mathilde of Belgium were also among the notable guests at the opening ceremony.
The couple, who look to have left their four children at home, waved to their delegation during the ceremony.
King Willem-Alexander of the Netherlands also proudly backed the Dutch athletes as they took part in the opening ceremony.
On day two of the Olympics, Frederik showed his support for the Danish national team as they faced Argentina in a handball event.
His cheering seemed to have paid off, as Denmark scored a 25-19 victory.