President Barack Obama has awarded the highest US civilian honour - the Presidential Medal of Freedom - to 16 people praised as "agents of change".
Recipients included South African human rights champion Archbishop Desmond Tutu and British scientist Stephen Hawking.
Tennis player Billie Jean King and former Irish President Mary Robinson were also honoured at the White House.
Posthumous medals were awarded to US gay-rights activist Harvey Milk and Republican Senator Jack Kemp.
Veteran US Senator Edward Kennedy was among the recipients, but his fight against brain cancer meant he was too ill to attend the ceremony.
Mr Obama said: "These extraordinary men and women, these agents of change, remind us that excellence is not beyond our abilities, that hope lies around the corner, and that justice can still be won in the forgotten corners of this world."
The Presidential Medal of Freedom is given to individuals who have "made an especially meritorious contribution to the security or national interests of the United States, or world peace, or cultural or other significant public or private endeavours".
Previous recipients have included former British Prime Minister Tony Blair and former South African President Nelson Mandela.
//BBC/