Taiwan Voting for Crucial Elections
Taiwan has begun voting in polls that could see the island elect its first female leader and set an uncertain course for future relations with China.
China sees the island as a breakaway province, which it has threatened to take back by force if necessary.
If Tsai Ing-wen leads her opposition Democratic Progressive Party to power, it will be a victory for Taiwan's pro-independence camp.
Eric Chu will stand for the ruling KMT, which oversaw improved ties with China.
China is bound to be watching these presidential and parliamentary election results closely.
Saturday's polls come just months after a historic meeting between the leaders of the two sides, the first in more than 60 years when outgoing Kuomintang (KMT) President Ma Ying-jeou met Chinese President Xi Jinping in Singapore in November for talks that were seen as largely symbolic.
But it is the flagging economy as well as Taiwan's relationship with China that are the key issues for voters.
If Ms Tsai, 59, wins it would be only the second-ever victory for the DPP.
The first was by pro-independence advocate Chen Shui-bian - during his time as president between 2000 and 2008 tensions escalated with China.
Ms Tsai, however, has not made her stance clear. A former scholar, she has said she wants to "maintain [the] status quo" with China.
But opponents say relations will deteriorate as she does not recognise the "one China" policy. She became chairwoman of the DPP in 2008, after it saw a string of corruption scandals.
She lost a presidential bid in 2012 but has subsequently led the party to regional election victories. She has won increased support from the public partly because of widespread dissatisfaction over the KMT and Mr Ma's handling of the economy and widening wealth gap.
Eric Chu, 54, is the mayor of New Taipei City and stepped up to become chairman of the party in October. The KMT is at risk of losing its majority in the legislature for the first time in history.
The former accounting professor is popular with young people in the party, but has not been able to change public opinion that is increasingly unhappy with the party's friendly stance towards China and the island's economic travails.
In 2014, hundreds of students occupied the parliament in the largest show of anti-Chinese sentiment on the island for years. Labelled the Sunflower Movement, protesters demanded more transparency in trade pacts negotiated with China.
Analysis: Cindy Sui, BBC News, Taipei
The election results could mark a turning point in Taiwan's democracy and relationship with China.
If the DPP wins, it means the island is moving towards a political system in which voters prefer to transfer power from one party to another, ending decades of mostly KMT rule.
That could make relations with China uncertain, because unlike the KMT, the DPP favours Taiwan's independence and does not recognise the Republic of China (Taiwan's official name) and the People's Republic of China as part of "one China".
A defeat for the KMT will present a serious challenge for Beijing. It was the Communists' bitter enemy during the civil war, but is now China's best hope, and perhaps only hope, of peacefully reunifying with Taiwan. The KMT fled to Taiwan after losing the war and its charter and leaders still favour eventual unification.
Beijing is closely watching the elections to gauge Taiwanese people's sentiments and what those sentiments will mean for its goal of reunifying with the last inhabited territory - following Hong Kong and Macau - that it feels was unfairly snatched from it by Japan as a colony in 1895, and then ruled separately by the KMT after the civil war.