Hillary Clinton is set to receive an honorary degree from one of the UK's oldest and most prestigious universities.
Donning a black gown, the former US secretary of state took part in a historic procession before she later gives the graduation address at a ceremony to mark the 600th anniversary of the founding of St Andrews University.
In her first foreign visit since her term as secretary of state ended in February, the politician will be honoured with a doctor of laws degree at Scotland's oldest university in recognition of her achievements as a politician and diplomat.
Mrs Clinton, whose husband Bill was president for eight years between 1993 and 2001, will receive the doctorate from the veteran Liberal Democrat politician and chancellor of St Andrews, Sir Menzies Campbell.
The award also marks her efforts to champion the causes of education, human rights, democracy, civil society and promoting opportunities for women around the world, according to the university.
The former US first lady, who lost to Barack Obama in the contest to be Democratic presidential candidate in 2008, is one of 18 prominent figures honoured by St Andrews today.
Honorary degrees are also being bestowed on the former Archbishop of Canterbury, Rowan Williams, classicist Professor Mary Beard, inventor of the world wide web Professor Sir Tim Berners-Lee, primatologist Dame Jane Goodall, particle physicist Professor Peter Higgs, anthropologist Professor Dame Marilyn Strathern and philosopher Professor Nancy Cartwright.
The university's principal and vice-chancellor, Professor Louise Richardson, said: "As one of the most influential women in the world, Hillary Clinton, as stateswoman, senator and policymaker, never shied away from tackling difficult questions, working to make the world a better place, inspiring others, speaking out for the voiceless and striving ever to excel.
"We are honoured that she will participate in our celebrations," she told the Press Association.
The Duke of Cambridge also congratulated the university on its 600th anniversary in a letter which was read out at the beginning of the ceremony.
Prince William, who met his wife Catherine while studying at St Andrews, wrote: "As a proud new father, I have come to think more than ever about the world our children will inherit; and the role of education, research and intellectual courage in our society has never seemed so important.
"For Catherine and me, the University of St Andrews is an emblem of these virtues.
"As proud patron of the Anniversary Appeal, I am delighted to offer my congratulations to all the university's honorary graduates today and my warmest congratulations to an institution that may be 600-years-old but which has never been as vital. Happy birthday, St Andrews."