What is the G8?A forum of heads of the leading industrialised democracies: Germany, France, Britain, Italy, Japan, the US, Canada and (since 1998) Russia.
The European Commission is also represented in all the sessions.
The first summit (France, 1975) was called to settle a dispute over currencies, but G7 meetings were soon expanded to discuss broad economic policy matters.
G8 does not have a fixed structure or permanent administration. It is up to the country that has the presidency to set the agenda and organise the summit.
What does the group do?
It meets to deal with the major economic and political issues facing members' domestic societies and the international community as a whole. Questions of macroeconomic management, international trade, relations with developing countries, East-West economic relations, energy and terrorism have also been of recurrent concern.
More recently, employment, the internet, the environment, crime and drugs, and a host of political issues ranging from human rights through regional security to arms control have been discussed.
Participants
The heads of state or government of the G8 take part. Chancellor Angela Merkel has also invited Brazil, China, India, Mexico and South Africa to take part in a so-called "outreach meeting".
A separate programme will involve ministers from Africa in the G8 summit. Five founder members of the Nepad group - Egypt, Algeria, Nigeria, Senegal and South Africa - will attend as will African Union president Ghana.
Venue
The seaside resort Heiligendamm, on the Baltic Sea coast, is the oldest seaside spa in Germany. It is part of the town of Bad Doberan in the state of Mecklenburg-Vorpommern. Inscribed on the outside of the Kurhaus (baths) - part of the Kempinski hotel and built between 1814 and 1816 - are the words: Hic te laetitia invitat post balnea sanum (Here happiness awaits you as you emerge healthy after bathing).
Security
A 2.5m-high (82ft) steel fence topped with razor wire has been placed in a ring around Heiligendamm and police will control access through airport-style X-ray machines. To prevent anyone from tunnelling beneath the fence, construction workers have rammed 50cm-long (20in) steel grating into the ground.