President Laura Chinchilla of Costa Rica has been sworn into office in San Jose.
Mrs Chinchilla, 51, took her oath of office at an open-air ceremony. She is the country's first female president.
The former vice-president has pledged to continue the free-market economic policies of her predecessor, Oscar Arias.
Leading the National Liberation Party, she won 47% of the vote in elections in February.
Attending the inauguration were the presidents of Mexico, Colombia, Ecuador and Georgia.