Htin Kyaw, a confidante of Nobel laureate Aung San Suu Kyi, has been sworn in as Burma's president.
He took the oath of office in a joint session of Burma's newly elected parliament on Wednesday with his two vice presidents.
The ceremony ushers the long-time opposition party of Ms Suu Kyi into government after 54 years of direct or indirect military rule.
Ms Suu Kyi's party, the National League for Democracy, won a landslide victory in November elections.
She is ineligible to be president herself but has said she will run the government from behind the scenes.
The constitutional clause that denied her the presidency excludes anyone from the position who has a foreign spouse or children.
Ms Suu Kyi's two sons are British, as was her late husband. The clause is widely seen as having been written by the military with her in mind.
Later on Wednesday, outgoing president Thein Sein will formally hand over the presidency to Mr Kyaw, who assumes office on Friday.