Last summer when we went to Haiti, I watched my nine-year old son jump a low fence to go play soccer with a group of boys on the beach at Cayes-Jacmel. My son did not speak Creole and the kids playing soccer did not speak English, but within minutes my son and the boys were playing a game together, laughing and participating in something that to me, had to do with a lot more than the sport. They were participating in friendship. And it was clear that it was a natural instinct: despite their language, color, and socioeconomic differences, they became instant friends.

Soccer, or fútbol as it is called in most parts of the world, is one of the most important sources of goodwill, and serves as both ambassador and therapist to children in countries where poverty, civil war and famine take a serious toll on their lives. The power of soccer as a vehicle for friendship cannot be understated. It is one of the most popular sports in the world, particularly with young children, and all that is required is a round ball and a little piece of flat land. That’s why for years, relief agencies like UNICEF have distributed soccer balls to children in slums and refugee camps.

But according to an article in The New York Times, soccer balls often go flat within 24 hours. The article focuses on the work of Tim Jahnigen and the company he co-founded, One World Football. A few years back, Jahnigen noticed the joy children got from the soccer balls they had—sometimes donated by a relief agency—but mostly improvised balls the children had created with trash. Jahnigen realized that what was needed was a soccer ball that wouldn’t go flat and would last, so he set out to invent one. With the support of Sting, Jahnigen developed the special soccer ball and named the company One World after the song, One World (Not Three), written by Sting when he was with the band The Police.

Read Related: How Play Can Help Schools Combat Bullying & Improve Learning

Last spring, CNN reported on CNN Hero Mark Kabban, who started a soccer program called Youth And Leaders Living Actively (YALLA), in 2009. It offers soccer training and tutoring to about 200 refugees in the San Diego, CA area. Because the children are from different parts of the world, ethnic and religious differences can lead to conflict, but as the soccer season progresses it’s all set aside.

Since 2006, Football United has been doing in Australia what Kabban is doing in California. Football United is a refugee youth soccer development program that offers programs and facilities for refugee youth to build skills and social networks. The program participants have come from different countries including Sudan, Ethiopia, Afghanistan, Bosnia, Sierra Leone, Liberia, Burma and Iraq.

Soccer is not like other games. It is considered the “World’s Game” as it is played in just about every country in the world, and there is not much need to speak the same language in order to play. And children who have lived through traumatic experiences like civil war or have spent time in refugee camps are susceptible to the effects of Post Traumatic Stress Disorder. Most psychologists agree that exercise is one of the best stress reducers, and still more believe that a good form of therapy for PTSD is play therapy. Soccer fits the shoe quite well.

Playing soccer helps form friendships, and keeps young people healthy and active. And for poor children around the world, soccer gives them the semblance of a normal childhood. Sometimes it is difficult for people in wealthy countries to imagine that in much of the world, kicking a ball around can make a huge difference in the lives of young people who have nothing.

One of my favorite times comes every four years when the World Cup is played. I always root for the underdogs, teams that have somehow managed to escape their humble beginnings to come to another country and play the game they love on the world stage. Unlike the Olympics, where it seems the same countries bring home the gold time after time, the World Cup feels like a truly open contest that brings the world together, much like the game of soccer itself. And it all starts when one child asks another if he wants to kick a ball.