President: Dilma Rousseff
Dilma Rousseff is the first woman to be elected as Brazil's president.
She was chief of staff to her predecessor, president Luiz Inacio Lula da Silva, and also his favoured successor.
In the October 2010 elections to succeed President Lula, she narrowly failed to win an outright majority in the first round.
The result meant Ms Rousseff faced the second-placed candidate, Sao Paolo mayor Jose Serra of the main opposition Social Democracy party, in a run-off vote on 31 October.
Ms Rousseff, 66, was little known to her compatriots until Mr Lula selected her as his favoured successor after a number of high-profile candidates were forced out by corruption scandals during his time in office.
She joined the government in 2003 as energy minister. In 2005, Mr Lula made her his chief of staff, a post she held until March 2010, when she launched her campaign for the presidency as the Workers Party (PT) candidate.
During the election campaign, Ms Rousseff made it clear that she represented continuity with the Lula government, under which millions of Brazilians saw their standard of living rise.
She is known to favour a strong state role in strategic areas, including banking, the oil industry and energy.
In 2013, she faced her biggest challenge so far, when people took to the streets in cities throughout the country to protest against corruption, inadequate public services and the expense of staging the 2014 football World Cup.
Dilma Rousseff was born in 1947 and grew up in an upper middle class household in Belo Horizonte, in the coffee-growing state of Minas Gerais.
Her father, Pedro Rousseff, was a Bulgarian immigrant.
Her seemingly conventional background changed in the mid-1960s, when she was in her late teens. She became involved in left-wing politics and joined the underground resistance to the military dictatorship that seized power in 1964.
She has said that she was never actively involved in armed operations, but in 1970 she was jailed for three years and reportedly tortured.
After her release at the end of 1972 she studied economics and went on to become a career civil servant.
Ms Rousseff is twice divorced and has one daughter.
In 2009, she was treated for and recovered from lymphatic cancer.