The world watched as Kate and Meghan exchanged a friendly kiss on the cheek as they greeted each other inside Westminster Abbey, while the brothers shook hands.
William also greeted Meghan with a kiss on the cheek. They then chatted as Charles and Camilla made their way in.
Meghan wore a cream coat over a cream print dress with a matching pillbox hat. But what she wasn't wearing has sparked speculation she is soon to give birth!
Kate opted for her red Catherine Walker coat dress, which she wore in New Zealand in 2014.
She topped it with a matching fascinator.
Before the Queen arrived, Meghan and Charles chatted together, while Kate and Camilla were deep in conversation.
Meghan and Kate gave expert curtsies as the Queen, who wore a beautiful purple coat dress and matching hat, walked in.
This year marks the 70th anniversary of the modern Commonwealth, which encompasses almost 2.4 billion people, a third of the world’s population.
And the young nature of the Commonwealth populations has led to Harry being named as the Youth Ambassador for the organization by his grandmother last year.
He and wife Meghan, 37, are making the Commonwealth a central part of their public life.