Catherine, who turns 30 on Monday, has become patron of Britain’s National Portrait Gallery and drug charity Action on Addiction, and royal patron of East Anglia’s Children’s Hospices and art charity The Art Room.
She is also becoming a volunteer with the Scout Association and will privately join some of their activities, especially in north Wales where William is based as a Royal Air Force search and rescue pilot.
The couple were married in April in a ceremony watched by billions of people around the world and are now known by the official titles Duke and Duchess of Cambridge.
“The Duchess’s first patronages and her volunteer position reflect Her Royal Highness’s personal interests in the arts, the promotion of outdoor activity, and supporting people who are in need of all ages, especially young children,” their office St James’s Palace said in a statement.
“The Duchess’s new roles reflect Her Royal Highness’s wish to support the Royal Family’s work in highlighting important causes in the charitable and voluntary sector and the arts.
“The Duchess has chosen to support organisations that complement the charitable work already undertaken by her husband.”
The statement said she would make a number of public and private visits across Britain in the coming months to the organisations she had chosen.
Catherine has been settling into “The Firm”, as the royal family is known, and attended the Christmas celebrations on Queen Elizabeth II’s country estate at Sandringham in eastern England for the first time in December.
The festivities were subdued however when the queen’s husband, Prince Philip, had to spend Christmas in hospital after having a heart operation.