Voting has opened in Germany's federal elections, with Chancellor Angela Merkel tipped to retain power.
She is seeking a fourth term in office and to keep her Christian Democrat party's (CDU) status as the largest presence in Germany's Bundestag.
The CDU's coalition partner, the SPD, is its main opponent. The right-wing AfD is likely to gain seats in parliament for the first time.
Polling stations opened at 08:00 local time (06:00 GMT) and close at 18:00.
The first exit polls are expected shortly after the close of voting.
The election is seen as important because it may result in six parties in the Bundestag - the German national parliament - for the first time since World War Two.
Such a result could mean a change in the makeup of the current governing coalition.
Key contenders
 
Angela Merkel: Widely expected to retain her seat, Mrs Merkel is seen internationally as a source of stability - having led Germany since 2005. Her decision to open Germany to asylum seekers during the peak of Europe's migrant crisis cost her politically, but she appears to have recovered
Martin Schulz: Leader of the centre-left SPD and Mrs Merkel's main rival, he is also her coalition partner - which has proved troublesome during the campaign, as he sought to criticise her politics
Alice Weidel and Alexander Gauland: The top candidates for the right-wing AfD. Achieving seats in the Bundestag - or potentially becoming the third-largest party, as some campaign polls suggested - would be a major victory
Martin Schulz, a leader of the Social Democrats (SPD) and a former president of the European Parliament, is Mrs Merkel's biggest rival for chancellor.
But Mrs Merkel, with 12 years of experience in the office, is widely expected to retain her position.
Among the parties expected to win seats is the right-wing nationalist, anti-Islam Alternative for Germany (AfD) party.
The party has so far held seats only in regional government but has grown in popularity during a campaign focused on immigration issues.
Other significant contenders include Die Linke (the Left), the Greens, and the Free Democrats (FDP).
Some 61.5 million people aged over 18 are eligible to vote in federal elections, which are held every four years.
There are two separate votes - one for a candidate in their constituency, and one for their preferred political party.
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