Loads of the world's most important politicians are meeting on 2 April in London, at a big meeting or summit called the G20.
But what exactly is it? Sonali's got the details.
What's going to happen in London in April?
The G20 members are going to meet for their yearly summit.
Which countries are in the G20?
Argentina, Australia, Brazil, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Mexico, Russia, Saudi Arabia, South Africa, South Korea, Turkey, the United Kingdom, America and the European Union.
Why isn't every country invited?
Because many people believe if there are too many countries in a group like this, then it's harder to make decisions and therefore, do any good.
Who is coming to the meeting?
The host, the British Prime Minister Gordon Brown, has invited the heads of government of all the members, including American President Barack Obama.
Finance Ministers, central bank governors from all the member countries, plus top officials from the European Central Bank, the International Monetary Fund and the World Bank will also come.
What are they going to talk about?
Top of the agenda will be the global money problems. The G20 talked about the problem at the last meeting in Washington DC in November 2008.
They will aim to come up with a plan of action to revive the global economy, to get more unemployed people working again and improve the way the global money systems work.
How can this event solve the problem of the global credit crisis?
The economies and banks of individual countries work very closely together. It makes sense for countries to talk to each other and co-ordinate their plans. The problem is that each country obviously wants the best for their own people, so it may be difficult to agree.
How are the decisions they make going to affect children and young people?
Their plans - good or bad - will affect everyone around the world - that includes all children and young people.
Because some of the plans will aim for longer term results, some things may not noticed until today's children and young people are adults.