Looking every inch the confident toddler, Prince George is pictured walking in an official photograph released to mark his first birthday.
With his arms outstretched and his eyes fixed on where he is going, the future king is striding ahead in the picture taken during a visit with his proud parents to the Sensational Butterflies outdoor exhibition at London's Natural History Museum.
The youngster will celebrate his first birthday on Tuesday when the Duke and Duchess of Cambridge are expected to hold a birthday party for him at their Kensington Palace apartment with close family and friends.
In the picture taken a few weeks ago, George is dressed in a pair of dungaree shorts from French label Petit Bateau, over a polo shirt-style top and shoes and socks.
Kate is wearing a green 1930s-inspired Budding Heart Silk Tea dress, by British brand Suzannah, which sells for £475.
She wore it under a green Erdem coat during her tour of New Zealand in April when she visited the town of Cambridge.
The Prince's blond hair has been swept across his head to create a stylish look and he has what his uncle Prince Harry has described as big chubby cheeks and the appearance of a "young Winston Churchill".
Press Association photographer John Stillwell took the picture and has photographed some of the key stages in the Prince's life, from his first public appearance the day after he was born to his christening last October.
Mr Stillwell said: "Prince George was very lively and very sure of himself and confident - a very determined young boy.
"When you have children yourself you don't realise they grow up in such a short space of time, it's always other people saying how big they've grown.
"So having seen him soon after he was born and at his christening three months later, he's now gone from a baby at his christening to a toddler, that's the biggest change.
"And who does he look like? I'd have to say his dad, William."
The birth of George Alexander Louis, known as His Royal Highness Prince George of Cambridge, was a global event, with the world's media camped for days outside the private maternity Lindo Wing of St Mary's Hospital in central London.
Kate gave birth at 4.24pm on July 22 to a son weighing 8lb 6oz, but the news was not announced to the waiting world until four hours later when members of the Royal Family spoke of their joy at the newest addition to their ranks.
The proud parents could not contain their happiness when they walked from the Lindo Wing and showed the world their son the following day.
Within a few months a gurgling George, carried by his father, arrived for his christening at the Chapel Royal, St James's Palace with the Queen, Duke of Edinburgh, other senior royals and Kate's family, the Middletons, sitting in the pews.
The young prince was taken on his first official tour in April, travelling to New Zealand and Australia - and stealing the limelight from his parents.
Commenting on George's birthday, a Kensington Palace spokeswoman said: "The family are going to be marking it privately with close family and friends at Kensington Palace."
Details of the birthday gifts George has received from the public have not been released but during the past 12 months he has been given a wide range of presents.
Well-wishers have sent him booties, baby blankets and knitted Aston Villa items - William's favourite football team - while official gifts received during visits and overseas engagements have included a number of adopted animals.
These include three slender-tailed meerkats named George, Alexander and Louis from the Dudley and West Midlands Zoological Society; a baby crocodile named George from the Chief Minister of the Northern Territory, which is kept at the Darwin Crocodile Park in Australia; and two fattened bulls, a heifer and a goat, from the Namunyak Women's Group, Kenya.