Teaming the fitted dress with glam sparkly Jimmy Choo heels and diamond Kiki McDonough hoop earrings, the Duchess also wore her hair in her signature blown out style.
The 37-year-old British royal previously wore the Barbara Casasola dress in 2016 when she presented the Art Fund Museum of the Year prize – and she also wore the Jimmy Choo heels earlier this year at the BAFTA Awards.
Earlier this week the Duke and Duchess of Cambridge – who are parents to Prince George, five, Princess Charlotte, four and Prince Louis, one – spent the day in Cumbria, in the Lake District, England where they got into the spirit of rural life by shearing sheep and meeting local villagers.
WATCH William and Kate get stuck into farm life during a trip to Cumbria: