Japan's Prime Minister Shinzo Abe is resigning after a year in office marked by scandals involving cabinet members and a disastrous election defeat in July.
Following are profiles of some possible successors.
Now No 2 in the ruling Liberal Democratic Party (LDP), Aso, 66, has served in key cabinet jobs including foreign minister and economic planning minister.
Like Abe, he comes from a venerable political family. His grandfather, then-Prime Minister Shigeru Yoshida, negotiated the peace treaty ending World War Two.
In 2006, Aso came second to Abe in the race for leadership of the LDP.
He appeals to fellow fans of "manga" comics but has stirred controversy with verbal blunders. A security hawk, Aso is a strong supporter of maintaining a tradition to allow only males to become emperor. For more details on Aso see
Tanigaki, 62, served as finance minister under Abe's predecessor, Junichiro Koizumi, and is well versed in economic policy.
The lower house lawmaker is seen as a relative dove on foreign policy.
A graduate of the elite University of Tokyo and a former lawyer, Tanigaki has said Japan will need to raise its 5 percent consumption tax to fix its huge public debt.
The son of a former education minister, Tanigaki is an avid cyclist. He once joked that he wore "tin underpants" -- a reference to his serious and stiff demeanour.
Fukuda, 71, was favoured by Abe's critics to succeed Junichiro Koizumi last year, but the lower house lawmaker never formally threw his hat in the ring.
During his tenure as chief cabinet secretary, a post he held for more than three years, Fukuda was dubbed the "shadow foreign minister". He has long stressed the need for good relations with Asian neighbours China and South Korea.
Known for having a short temper, Fukuda comes from a political family. His father, Takeo Fukuda, was prime minister.
The first to announce his candidacy, Finance Minister Nukaga, 63, was appointed defence minister in 1998 but resigned after a few months in office in a procurement scandal.
Three years later he stepped down as economics minister over a political "money for influence" scandal. Reappointed defence minister in October 2005, Nukaga is an expert in security issues.
Japan's foreign minister, Machimura, 62, has been education minister several times and like Abe is a proponent of education reform to revive patriotism.
Machimura also shares Abe's goal of a bigger say for Japan in global affairs. Last year he headed a ruling party team that called for stronger national intelligence-gathering capabilities.
He is a member of a group of conservative lawmakers who in June urged China to remove photographs and exhibits from museums that they say distort the truth about Tokyo's actions before and during World War Two.
A former defence chief, construction minister and deputy party leader, 70-year-old Yamasaki returned to parliament in a 2005 by-election after losing his seat in a 2003 election.
A long-time ally of Abe's predecessor, Junichiro Koizumi, Yamasaki angered the government in January by visiting North Korea for talks without an official mandate from Abe.
Born in what was then a Japanese-occupied area of China, Yamasaki is a graduate of Tokyo's prestigious Waseda University.
The 58-year-old health minister is a former academic and television commentator, well-known for his harsh criticism of both the government and bureaucrats over mishandling of the public pensions system.
The multilingual Masuzoe wrote a series of magazine articles about his experiences caring for his mother, who suffered from dementia in the last years of her life.
Masuzoe has led a tumultuous personal life and has been married three times, once to Satsuki Katayama, now a fellow LDP lawmaker.
Speculation refuses to die that Koizumi, 65, who served as prime minister for five years, could be called back to take over the leadership.
He topped a newspaper poll last month as the voters' choice to succeed Abe and still serves in parliament, but an LDP executive quoted his as saying on Thursday: "I 100 percent would not run."
A popular maverick who was rarely out of the media eye while in office, Koizumi vowed to carry out reforms and shake up the ruling party. In 2005, he led the LDP to a landslide victory in a lower house election.
But Koizumi himself said last year just before leaving office that he would enjoy his freedom. When asked if he was sorry to leave his official residence, he was quoted as saying "No, no, I will be free."