The landslide victory of a television comedian with no political experience to the Ukrainian presidency was only possible because of a fever for reform in that country, over everything from energy prices to rampant corruption.
But how Volodymyr Zelenskiy might achieve all that when he takes office next month is unclear.
He didn't give many specifics on the campaign trail, and parliament is already trying to curb his new power.
Reuters Matthias Williams, in Kiev: (SOUNDBITE) (English) MATTHIAS WILLIAMS, CHIEF CORRESPONDENT FOR UKRAINE, SAYING: "Ukraine operates under a mixed political system.
That means that though Volodymyr Zelenskiy won the presidency by a huge margin defeating the incumbent President Petro Poroshenko, he does in fact at the moment have no MPs in parliament because parliamentary elections are due to take place in October.
That means that he will be somewhat hamstrung in the kind of policies that he might want to get through if parliament doesn't approve of them.
Now when it comes to October he will probably get a healthy showing for his party, he's on course to perhaps take the most seats in parliament.
But on the other hand he probably won't get a majority, which means that he will have to find some sort of ally to partner with should he want to form a government as well." So for now Zelenskiy, who used to play a president on television, is alone in his real-life parliament.
And they're hostile.
Just two days before the election one opposition party proposed new legislation that would make it easier for them to impeach a president.
It's also not clear how he'll keep promises such as removing lawmakers' immunity from prosecution - because those same lawmakers will need to approve it.
(SOUNDBITE) (English) MATTHIAS WILLIAMS, CHIEF CORRESPONDENT FOR UKRAINE, SAYING: "Volodymyr Zelenskiy is indeed something of an unknown quantity both for the voting public and to investors as well.
One of the strengths of his campaign was sometimes that he was quite vague about the things that he said he would do in office.
But one thing is for sure is that he wants to fight corruption, that he would keep Ukraine broadly on a pro-Western course, but quite how he will do that manage the very high expectations the voters will have is another question."