Thailand holds an election on May 14 after nearly a decade of a government led or backed by its royalist military after a coup in 2014.
Below is a rundown of what to expect.
WHAT'S BEING DECIDED?
Roughly 52 million of Thailand's 65 million population are eligible to cast votes for members of a new 500-seat house of representatives for the next four years.
Voters have two ballots, one for a local constituency representative and the other for their preferred party on a national level. There are 400 seats for winning constituency candidates and 100 party seats allocated on a proportional representation basis.
HOW WILL A LEADER BE CHOSEN?
Parties winning more than 25 seats can nominate their prime ministerial candidate, although it is likely parties will strike deals between them to back certain candidates.
Those candidates will be put to a vote, likely in August, of the bicameral legislature comprised of a newly elected 500-seat lower house and a 250-seat Senate comprised of members appointed by a military junta.
To become prime minister, the winning candidate must have the votes of more than half of the combined houses, or 375 members.
WHO ARE THE MAIN CONTENDERS?
The election will be the latest bout in a long-running battle between parties backed by a conservative establishment with connections to the military and key institutions, and a progressive, pro-business opposition with a track record of wooing working class voters and winning every election in the past two decades.
Pheu Thai, a party controlled by the billionaire Shinawatra family, has a big lead in opinion polls as it did in previous elections, followed by another opposition party, Move Forward, which is seeking to mobilise youth voters.
They will go up against two parties led by former army chiefs involved in coups, incumbent Prime Minister Prayuth Chan-ocha of the newly formed United Thai Nation party, and his mentor Prawit Wongsuwan, of the ruling Palang Pracharat party.
Both parties draw backing from the urban middle classes and are regarded as representing the interests of Thailand's nexus of old money aristocrats and military elites who have long influenced politics.
An important contender is Bhumjaithai, a regional heavyweight whose seats could be crucial in determining who forms a government. The party's stature has grown with its successful push to make Thailand Asia's first country to legalise the sale of cannabis.
WHEN WILL THE RESULTS BE KNOWN?
Voting ends at 5 p.m (1000 GMT) local time on Sunday and the election commission says unofficial results should be released that same evening. It aims to certify 95% of the votes or 475 of the 500 seats, within 60 days, or by July 13.
The commission and an alliance of media organisations are expected to provide updates on the vote count in the hours after polling stations close.
WHAT HAPPENS AFTER THAT?
It might be weeks, possibly several months, before Thailand gets an idea of what it's next government will look like, depending on the outcome of the election.
An outright majority or even a landslide may not be enough to form a government and alliances with other parties will most likely be required.
Thailand's constitution was re-drafted by the military in 2017 in what many experts say was an attempt to neuter the power of parties that win elections. It prescribed an appointed Senate, of which the majority of members have sided in votes with the ruling, military-backed parties.
(Editing by Kim Coghill)
