The challenger Andris Berzins has won the presidential election in the Baltic state of Latvia, in a second round of voting.
Mr Berzins defeated incumbent Valdis Zatlers, winning the support of 53 MPs out of 100 in a parliamentary ballot.
The outgoing president had called for radical reforms to curb the corrupting influence of oligarchs.
Mr Berzins, 66, is a former banker turned politician in the Greens and Farmers' Union.
President Zatlers, 56, had been widely expected to win the vote, until he accused lawmakers last Saturday of being soft on corruption and called a referendum on the dissolution of parliament.
His outburst came after parliament stopped the country's anti-corruption bureau from searching the home of a powerful local politician who has been engulfed in scandal.
The confrontation plunged Latvia into political turmoil just as the country was recovering from a near economic collapse.
Latvia is struggling to meet the conditions of a massive loan from the International Monetary Fund and European Union.
In Latvia, it is parliament that chooses the president.
To win, a candidate must secure an outright majority of the vote.
The election had been scheduled for July, when President Zatlers' term ended.
"Thank you for the honour you have shown me," Mr Berzins told parliament after the vote.
Andris Berzins was active in politics after Latvia regained independence from the former Soviet Union in 1991.
Later he ran a leading bank until 2004, and then became head of the country's chamber of commerce.
He returned to parliament just last year, in October.
The outgoing president, Mr Zatlers, is an orthopaedic surgeon by training. He became president in July 2007.