The group held a summit hosted jointly by Germany and France.

Over the weekend, the leaders of many countries met for two days of meetings in France and Germany. The meeting, called a summit, was for members of NATO, the North Atlantic Treaty Organization. A treaty is an agreement between nations. President Barack Obama went to the summit as part of his first major trip overseas as president. Why do you think it's important for presidents to travel overseas and meet with other leaders? President Obama attended the summit along with leaders from all 26 countries that are members of NATO. Here you see the leader of NATO, whose name is Jaap de Hoop Scheffer. His official title is secretary general. He was in charge of the meeting, which was also hosted by the leaders of France and Germany. The other picture here shows the outside of NATO's headquarters in Brussels, Belgium. The flags of the member nations are displayed outside the building. Can you recognize any of the flags in this picture?

This is the first time a NATO summit has been hosted together by two countries. It is part of NATO's celebration of its 60th anniversary. But the summit is also a chance for its members to discuss some very big challenges the organization is facing. We'll learn more about that shortly. First, let's take a look at how NATO came to be.