The article looks at how the EU expanding to include former Soviet countries affects different regions. They used a model to see how this expansion and deeper EU-FSU integration impact economies. The study shows that EU enlargement benefits all EU regions without harming countries outside the Union much. However, closer EU-FSU integration has a different effect. For it to benefit former Soviet countries, they need to improve productivity through better institutions or more foreign investment. But this agreement isn't good for many parts of the EU and the rest of the world.