- The six largest countries of the world: Canada, France, Germany, Japan, the United Kingdom, and the United States.
- The six largest countries of the European Union, ministers from which sometimes meet to discuss issues of common concern. The countries are France, Germany, Italy, Poland, Spain, and the United Kingdom.
- A group of countries that has met several times to resolve disagreements that prevent progress in the Doha Round. The group includes Australia, India, Japan, the United States, the European Union, and either Brazil or China (I've seen both mentioned).