He looks likely to enjoy plenty of support for his political agenda in Congress after his Republican Party regained control of the Senate.
In his victory speech, Trump vowed he would “govern by a simple motto: Promises made, promises kept. We’re going to keep our promises”.
But in some cases, he has given little detail of how he might achieve his aims.
Asked in 2023 by Fox News whether he would abuse his power or target political opponents, he replied he would not, “except for day one”.
“No, no, no, other than day one. We’re closing the border, and we’re drilling, drilling, drilling. After that, I’m not a dictator.”
1. Deport undocumented migrants
While campaigning, Trump promised the biggest mass deportations of undocumented migrants in US history.
He also pledged to complete the building of a wall at the border with Mexico that was started during his first presidency.
The number of crossings at the US southern border hit record levels at the end of last year during the Biden-Harris administration, before falling in 2024.
Experts have told the BBC that deportations on the scale promised by Trump would face huge legal and logistical challenges – and could slow economic growth.
2. Moves on economy, tax and tariffs
Exit poll data has suggested the economy was a key issue for voters. Trump has promised to “end inflation” – which rose to high levels under President Joe Biden before falling again. But a president’s power to directly influence prices is limited.
He has also promised sweeping tax cuts, extending his overhaul from 2017. He has proposed making tips tax-free, abolishing tax on social security payments and shaving corporation tax.
He has proposed new tariffs of at least 10% on most foreign goods, to cut the trade deficit. Imports from China could bear an additional 60% tariff, he has said. Some economists have warned that such moves could push up prices for ordinary people.
3. Cut climate regulations
During his first presidency, Trump rolled back hundreds of environmental protections and made America the first nation to withdraw from the Paris climate agreement.
This time, he has again vowed to cut regulations, particularly as a way to help the American car industry. He has constantly attacked electric vehicles, promising to overturn Biden’s targets encouraging the switch to cleaner cars.
He has pledged to increase production of US fossil fuels – vowing to “drill, drill, drill” on day one in favour of renewable energy sources such as wind power.
He wants to open areas such as the Arctic wilderness to oil drilling, which he argues would lower energy costs – though analysts are sceptical.
4. End Ukraine war
Trump has criticised the tens of billions of dollars spent by the US on supporting Ukraine in its war with Russia – and has pledged to end the conflict “within 24 hours” through a negotiated deal.
He has not said what he thinks either side should give up. Democrats say the move would embolden President Vladimir Putin.
Trump wants the US to disentangle itself from foreign conflicts generally. Regarding the war in Gaza – Trump has positioned himself as a staunch supporter of Israel, but has urged the American ally to end its operation.
He has also pledged to end the related violence in Lebanon, but gave no detail on how.
5. No abortion ban
Against the wishes of some of his supporters, Trump said during the presidential debate with Kamala Harris that he would not sign into law a national abortion ban.
In 2022, the nationwide constitutional right to abortion was overturned by the Supreme Court, which had a majority of conservative judges following Trump’s first presidency.
Reproductive rights became a key campaigning topic for Harris, and several states approved measures to protect or expand abortion rights on polling day.
Trump himself has regularly said states should be free to decide their own laws on abortion, but struggled to find a consistent message of his own.
6. Pardon some Jan 6 rioters
Trump has said he will “free” some of those convicted of offences during the riot in Washington DC on 6 January 2021, when his supporters stormed the Capitol building in an effort to thwart the 2020 election victory of Joe Biden.
Several deaths were blamed on the violence, which Trump was accused of inciting.
He has worked to downplay the riot’s significance and recast the hundreds of supporters who were convicted as political prisoners.
He continues to say many of them are “wrongfully imprisoned”, though has acknowledged that “a couple of them, probably they got out of control”.
7. Sack Special Counsel Jack Smith
Trump has vowed to sack “within two seconds” of taking office the veteran prosecutor leading two criminal investigations against him.
Special Counsel Jack Smith has indicted Trump over alleged efforts to overturn the 2020 election, and over his alleged mishandling of classified documents.
Trump denies any wrongdoing, and managed to prevent either case from coming to trial before the election. He says Mr Smith has subjected him to a “political witch hunt”.
Trump will return to the White House as the first-ever president with a criminal conviction, having been found guilty in New York of falsifying business records.
