The 31-year-old royal looked stunning in a mint green Mulberry coat and nude LK Bennett heels as she honoured the achievements of over 400 scouts before attending a service at St George's Chapel in Windsor.
Catherine, who is currently six months pregnant, was joined by TV presenter Bear Grylls, who was made a Chief Scout in 2009.
Speaking about the Duchess, the 34-year-old adventurer said: "She's an inspirational role model and such a generous volunteer and everyone is so excited to have her in the scouting family. Many people have followed her lead and are getting involved and enjoying the adventure."
Kate, who is a trained scout volunteer, awarded scouts between the ages of 16-25 for their community service work and cradled her bump as she spoke with volunteers and Grylls.
The Duchess recently braved the cold during a public visit to the Great Tower Scout Camp in Cumbria where she cooked bread over a camp fire with volunteers.
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