Kate Middleton joined members of the royal family at Windsor Castle on Monday for the Order of the Garter service, and she looked as perfectly polished as ever in a black and white Catherine Walker coat that was perfect for the occasion. The duchess has turned to the British-based fashion house many times in the past, and it's easy to see why. Catherine Walker was also a favorite of Princess Diana, and can always be relied upon to create timeless, elegant pieces that are perfect for formal royal engagements.
This time around, Kate chose a single-breasted white fit-and-flare coat with black trim, and accessorized with a black Lock & Co. hat and a simple clutch bag. Pearl earrings finished the look, and pearls definitely seemed to be a theme for many of the royal attendees: the Countess of Wessex also wore pearl drop earrings, while the Duchess of Cornwall chose an ornate pearl and pink topaz choker. The British royals were joined by Queen Máxima of the Netherlands and Queen Letizia of Spain, whose husbands were invested into the Order of the Garter in an earlier ceremony. See all the photos of this stylish group ahead, and get a closer look at Kate's chic ensemble.