The Japanese general election on 11 September will be one of the most keenly fought in years, with politicians and much of the public divided by Prime Minister Junichiro Koizumi's plan to reform the post office.
Junichiro Koizumi (l) has been in power since 2001
Q: What is at stake?
The overriding issue is the state of the Japanese economy, which has stagnated for years but has recently shown signs of recovery.
Prime Minister Junichiro Koizumi has made privatisation of Japan Post the cornerstone of the economic reforms he has pursued since he first became premier in 2001.
Q: Why are the elections being held early?
Mr Koizumi called the snap election after the defeat of his post office proposals.
The bill scraped through the lower house by a margin of five votes on 5 July, but was defeated in the upper house on 8 August, when 30 ruling Liberal Democratic Party lawmakers failed to back it.
Mr Koizumi has said the election should be seen as a referendum on his reform agenda and insists on support for postal privatisation from ruling party candidates.
Q: Why is postal reform such a big issue?
Japan Post is a huge organisation, with some 25,000 offices and around a quarter of a million employees, who are civil servants. As a state-owned savings bank with more than $3 trillion in assets, it is possibly the largest financial institution in the world.
Mr Koizumi's privatisation bill proposed splitting Japan Post into four separate entities - mail delivery, postal savings, life insurance and post offices.
Advocates of reform say privatisation will revitalise the economy by making more efficient use of the service's huge funds for investment.
Critics say it will lead to massive job losses and a decline in services for rural communities.
The issue has created severe divisions within the ruling LDP.
Q: How does the electoral system work?
The House of Representatives is the lower house of Japan's bicameral parliament, the Diet. There are 480 seats, and members are elected for a term of four years.
241 needed for a majority
300 elected from single-seat constituencies
180 elected by proportional representation
The 11 September election will be the fourth since the system of voting for the lower house was changed from a multi-seat constituency system to a mixed system of single-seat constituencies and proportional representation.
Of the 480 members, 300 are elected from single-seat constituencies and the remaining 180 by proportional representation.
Voters cast two ballots: first, one for an individual candidate in the single-seat constituency, and second, one for a political party in the proportional representation election.
Q: What is the current composition of parliament?
The LDP-led ruling coalition won a reduced majority in the November 2003 polls.
When parliament was dissolved on 8 August, the LDP had 249 seats and its coalition partner New Komeito had 34. The main opposition party, the Democratic Party of Japan (DPJ), had 175 seats, the Japanese Communist Party had nine and the Social Democrats six.
The remaining seats belonged to independents, small parties or were vacant.
Q: What does the ruling coalition stand for?
The ruling coalition consists of two parties: the LDP and New Komeito.
The LDP was founded in 1955 and apart from a few years in the mid-1990s has held power continuously since then. Mr Koizumi has led the party since April 2001.
Apart from the postal reforms, key points in the LDP's manifesto include boosting ties with the US and enacting legislation to enable Japanese troops to take part in multinational operations.
The New Komeito Party, headed by Takenori Kanzaki, formed a ruling coalition with the LDP in 1999. New Komeito backs the LDP's economic reform plans, but opposes Mr Koizumi's controversial visits to the war-linked Yasukuni Shrine.
Q: What does the opposition stand for?
The LDP's main rival is the Democratic Party of Japan (DPJ), led by Katsuya Okada. Founded in 1996, the party has since then steadily gained strength.
Seats held on 8 August 2005
Liberal Democratic Party - 249
New Komeito - 34
Democratic Party of Japan - 175
Japanese Communist Party - 9
Social Democratic Party - 6
Key points in the DPJ manifesto include a pledge to cut government spending on large-scale public works projects.
It would keep Japan Post as a public corporation, but scale down the savings service by placing a cap on individual deposits.
It also wants to withdraw Japanese troops from Iraq by December, but remains supportive of the US-Japan alliance.
The Japanese Communist Party opposes revision of the war-renouncing Article 9 of the constitution. It wants to terminate the Japan-US alliance and close US bases in Japan.
The Social Democratic Party has in recent years steadily lost support to the DPJ. Formerly the Japan Socialist Party, it promises to keep Japan Post intact, increase child benefit and raise income tax. It wants to withdraw Japanese troops from Iraq.
Q: What is the role of the LDP rebels?
Of the 37 lower house LDP deputies who opposed the postal reform bill in the first vote on 5 July, four have decided not to stand in the election and one plans to run for a proportional representation seat.
The remaining 32 will face pro-privatisation candidates backed by the LDP in their constituencies. These pro-privatisation candidates - many of them high-profile non-party supporters of Mr Koizumi - have been dubbed "LDP assassins".
The LDP rebels take issue with Mr Koizumi's maverick style of leadership, with one likening the premier's decision to call a snap election to "a suicide bombing".
Two new parties have recently been formed by LDP rebels: the People's New Party, led by Tamisuke Watanuki, and the New Party Nippon, led by Yasuo Tanaka.
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.