The newlyweds, Prince Harry and Meghan, delayed their honeymoon in order to attend Prince Charles's 70th birthday celebration.
For her first event as an official member of the royal family, Meghan took note from her sister-in-law, the Duchess of Cambridge, donning a sophisticated dusty pink dress by one of the mum-of-three's favourite brands, Goat.
And the independent British brand quickly felt the full might of 'The Meghan Effect'.
The 'Flavia Dress' is described on Goat's website as "beautifully fluid and feminine", and it comes with a mid-range price tag of £590.
The label's site consequently crashed, as soon as details of Meghan's look emerged, with the brand taking to Twitter to say: "Our website is currently down due to a high volume of traffic".
Although Meghan is no stranger to selling out products, she hasn't crashed a website since the couple's engagement announcement, when her bridal-inspired coat caused a shopping frenzy for Canadian brand Line The Label.
Our website is currently down due to a high volume of traffic. We sincerely apologise & hope to rectify this as soon as we can.— Goat (@Goatfashion) May 22, 2018
It wasn't long, too, before the dress sold out altogether; the timeless nude number going from being in stock in all sizes, from 8-18, to completely out of stock overnight.
It is, though, still available in black.
In a departure from her usual modern style, the Duchess adhered to the royal fashion rules at the Buckingham Palace garden party by sporting a clutch bag and skin coloured tights. Despite this, it's clear that many are still keen to get their hands on the new royal's wardrobe.