North and South Korea have announced that they will march together in the Winter Olympics under the same flag.
The Olympics are being held in South Korea and start today.
The two countries have agreed that their athletes will march under one flag of Korea, rather than their separate countries' flags.
They also agreed to have a joint women's ice hockey team.
It doesn't sound like a very big deal, but North and South Korea have a lot of history.
They are two separate countries, who have been enemies since a war that started in 1950.
There has been tension between the two countries ever since.
Recently, senior politicians from both side have started talking to each other again.
Both countries say the Winter Olympics are a way for the two countries to show the world that they are getting along a little better.
However, at the same time, North Korea has been building up its weapons.
And the country's leader Kim Jong Un has also had some serious arguments with US President Donald Trump.
So it is too early to say whether North and South Korea will remain friendly.
But lots of people hope that a friendly Olympics will help keep the countries talking.
If you'd like to know more about what's happening in North Korea, check out our guide.