What does the G7 actually stand for? And what is at stake at the annual summits in idyllic surroundings far from the centres of government?
Seven essential things to know about the G7:
1) The 1975 global economic crisis led German Chancellor Helmut Schmidt and French President Valery Giscard d'Estaing to the idea of a summit drawing in the major industrial powers. The aim was to discuss the state of the world economy and to seek approaches to solving global problems.
2) During the first summit at the Chateau de Rambouillet near Paris, the heads of state and government of France, Germany, the United States, Britain, Japan and Italy met. Canada was added a year later, creating the Group of Seven (G7) from the Group of Six (G6).
3) Russia became a full member in 2002, although the G8 survived only until 2013. Russia's annexation of the Crimea in 2014 led to the planned summit in Sochi on the Russian side of the Black Sea being abandoned. Instead, the G7 met without Russia in Brussels. There is currently no move for Russia to re-join.
4) When it was set up, the G7 was home to the seven leading industrial nations of the world. This is no longer the case. Taking into account the top 10 world economies, China at number two and Brazil at number seven are left out.
5) Global economic issues were the focus in the initial years, and the summits were also known as global economic summits. These days international crises tend to take centre stage.
6) The G7 takes no mandatory decisions. The closing Leaders' Declaration is not binding in nature. The main point of the meetings is to exchange ideas on the most important issues facing the world.
7) Under the rotating presidency, the summit takes place in a different member country each year. Last year German Chancellor Angela Merkel hosted the summit at Schloss Elmau in Bavaria. This year the summit is being held in Ise-Shima in Japan.