Last night, the Duke and Duchess of Cambridge were driven to Her Majesty's white-tie diplomatic reception, held at Buckingham Palace. The occasion, like a state banquet, requires ladies to wear tiaras.
This is excellent news for Catherine's fans, who rarely see her wearing one.
Her Royal Highness chose to wear the Cambridge Lover's Knot tiara, frequently worn by her late mother-in-law, the Princess of Wales.
The tiara was originally made for Queen Mary in 1914 by Garrard, the same jeweler that created Diana's blue sapphire engagement ring (now worn by Catherine).
The piece was left to Queen Elizabeth, who loaned the it to Diana for several occasions.
This was Catherine's second diplomatic reception; in 2013 she wore the same ice blue Alexander McQueen dress with the Queen Mother's Lotus tiara. This October, she chose the tiara again for the China state banquet.
Today, William and Catherine took part in ICAP's charity day, where they hopped on the phone and brokered donations from clients.
A portion of the donations earned today go to William and Catherine's charities, SkillForce, Sportsaid and Place2Be,
For the occasion, Catherine recycled her peplum L.K. Bennett outfit from 2012, when she accompanied the Queen and Prince Philip on a Diamond Jubilee visit to Leicester, England.
Her jewelry comes from Mappin & Webb's "Empress" collection.
The hair's a bit shorter too.