Twelve candidates are contesting Poland's presidential election on Sunday. The top two go to a second round if no candidate wins at least 50% of the vote in round one. BBC Monitoring profiles the four frontrunners.
Donald Tusk is favourite according to most polls. He chairs the Civic Platform, which came second in last month's parliamentary election.
A Solidarity activist in the 1980s, he styles himself as a "man of principles" and pledges to tackle what he sees as Poland's most pressing problem: corruption.
Born in Gdansk in 1957, he was brought up by his mother, a nurse, after his father died.
His interest in politics began after he watched police open fire on protesters in Gdansk in December 1970. He was active in the Solidarity movement during martial law.
After Communism fell in 1989, he became chairman of the Liberal Democratic Congress, a coalition partner in the Solidarity-led governments of the early 1990s.
In 1997 Mr Tusk was elected deputy speaker of the Senate, or upper house.
After failing in a bid to lead his party, the Freedom Union, he formed a new centre-right group, which later became the Civic Platform.
The Civic Platform won 63 seats in parliament in September 2001 and Mr Tusk became deputy speaker in October.
He was elected party chairman in June 2003 and is seen as a moderate with a non-combative style.
Warsaw mayor Lech Kaczynski is running second in the opinion polls. He and his twin brother Jaroslaw lead the Law and Justice party, which won most votes in parliament last month.
Born in Warsaw in 1949, the brothers shot to fame at the age of 12 as stars in the film Two Boys Who Stole The Moon.
Lech followed his brother into the anti-government movement in the late 1970s and served as an adviser to the strike committee at the Gdansk shipyard during the August 1980 Solidarity-led protests.
He was arrested under martial law in December 1981 and remained in prison until the following autumn.
In February 1989 he participated in the landmark roundtable negotiations between Solidarity and the government that resulted in partly free elections.
He and his brother found themselves outside mainstream politics in the early 1990s after falling out with the Solidarity leader, by now Polish president, Lech Walesa.
Lech Kaczynski was thrown a political lifeline when Prime Minister Jerzy Buzek made him justice minister in June 2000.
Despite his popularity he was fired 13 months later following a row with the secret service over allegations of official corruption.
In April 2001, the brothers established the Law and Justice party. Lech was elected Warsaw mayor in November 2002.
He has focused on the traditional values of the Catholic Church. Earlier this year, he refused permission for a gay rights parade in Warsaw.
Andrzej Lepper is the colourful leader of the eurosceptic Self-Defence party, which came third in the recent parliamentary poll.
A pig farmer with a reputation for plain-speaking, he has contested two previous presidential elections.
He came ninth in 1995, with just 1% of the vote, and fifth five years later with 3%.
Seldom out of the headlines, he was one of three Self-Defence MPs indicted earlier this year for dumping imported German grain onto the tracks of a Warsaw rail depot.
Born in 1954, he purchased a neglected farm at the age of 26 and continues to farm to this day.
Though a member of the Communist party since his 20s, he became active in politics only after his farm fell into debt in the early 1990s.
He organised protests on behalf of other debtors, which eventually led to the formation of a populist peasant trade union called Self-Defence.
He became leader of the union's newly established political arm, also named Self-Defence, the following year. Self-Defence failed to win any seats in parliament until 2001.
He served as deputy speaker of the Sejm in 2001, but was sacked after a month after a heated debate in which he accused cabinet members of taking bribes.
Marek Borowski, born in Warsaw in 1946, worked for the communist administration during the 1980s and was finance minister in one of the early post-communist governments.
He established his own political party, the Social Democracy of Poland, last year.
Inspired by his father, chief editor of an influential newspaper in the early post-war years, Marek enrolled in the Union of Socialist Youth before becoming a member of the communist Polish United Workers Party in 1967.
He was expelled from the party after he organised a student protest in March 1968. He worked at a Warsaw department store before rejoining the party in 1975.
Seven years later he joined the internal market ministry where he allied himself with communist reformers.
As deputy internal market minister in the first post-communist government, he was active in pushing through radical economic change.
He became Prime Minister Waldemar Pawlak's finance minister in 1993 but resigned within a year over the sacking of one of his deputies.
By the late 1990s, Mr Borowski was a senior figure in the Democratic Left Alliance (SLD) and was elected Sejm Speaker after the party's electoral success in 2001.
In June 2002 opposition parties accused him of bias and suppressing debate. He survived a bid to call a no-confidence vote and continued in post until April 2004.
Mr Borowski left the SLD in March 2004 to form the Social Democracy of Poland, which failed to win any seats in the recent Sejm elections.
BBC Monitoring selects and translates news from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages. It is based in Caversham, UK, and has several bureaus abroad.