By Jonathan Marcus Diplomatic correspondent, BBC News, Heiligendamm

Angela Merkel was in no doubt that the summit had been a success

It was a summit of contrasting images.

There were the new arrivals on the diplomatic scene - the new French President, Nicolas Sarkozy, and Japanese Prime Minister Shinzo Abe.

There was the host of the gathering - German Chancellor Angela Merkel, herself a relative newcomer onto the international scene, who nonetheless steered the proceedings with some success.

There was the sight of the US President, George W Bush, visibly shifting his ground, affirming his support for measures to cut greenhouse gases.

And there was his Russian counterpart, Vladimir Putin, seemingly breaking the diplomatic ice with his suggestion - actually, he was acquiescing to a long-standing US invitation - that Russia and the US pursue a missile defence system together.

Largely beyond the perimeter wire - thankfully for the organisers - there were the demonstrators, some dressed in clown outfits, mainly young, mainly well-meaning.

They were confronted by thousands of police with hundreds of vehicles - clearly a message for fossil fuel use there.

Post-mortems

But now with the G8 summit over, the post-mortems are under way.

[The climate deal] was not only the product of some skilful diplomatic cajoling, but also a sign that the climate back home in America is also changing to be much more aware of environmental issues Excerpts of summit agreements

What do the long and wordy declarations really amount to?

Is this just yet another failed opportunity, as many of the representatives of development campaign groups and lobbying organisations would have us believe?

Inevitably this summit, like so many others, has not solved the world's problems.

But then it was never intended to. In policy terms summits are part of a journey, not a destination in themselves.

The G8 leaders were joined by their counterparts from key developing economies like China and India and from several African countries - yet again a demonstration that global issues require global action and that the days are long gone when a rich nations' club can seek stewardship of the world.

Many things could not be resolved here, anyway.

Central issues relating to trade and development in Africa are the preserve of the World Trade Organisation.

A new climate treaty to replace the Kyoto Protocol, whose commitments expire in 2012, needs a UN framework with not just the US, but China, India and key developing economies on board.

Commitment to Africa

So what was achieved?

Africa and climate change were at the core of Angela Merkel's agenda.

On climate change, President Bush did indeed move in the direction of a global treaty on greenhouse gas emissions with teeth.

Promises made at Gleneagles in 2005 have so far not been met

This was not only the product of some skilful diplomatic cajoling, but also a sign that the climate back home in America is also changing to be much more aware of environmental issues.

On Africa, there was an acceptance that past commitments on aid had not been met.

Targets were reaffirmed, but there were decisions to actually begin allocating money to specific programmes, not least the $60bn ear-marked for combating HIV/Aids, malaria and tuberculosis.

Of greater importance still is the fact that there was a lot of talk here about establishing mechanisms to try to ensure that there is no back-sliding on commitments.

Japan, the host of next year's gathering, said it would again put Africa high on the summit agenda - the continent's problems are effectively becoming institutionalised as a permanent feature of the G8's work.

Seaside sun

Apart from these two big summit themes, think of an international problem and it has been touched on here.

George Bush and Vladimir Putin held bilateral talks at the summit

Darfur, Kosovo, missile defence, Middle East peace, North Korea's nuclear programme and Iran's too, all figured.

Fears that this summit would be overshadowed by tensions between Russia and the US proved unfounded, but many thorny problems involving Moscow, missile defence and Kosovo, for example, remain far from resolved.

The seaside sun did though seem to thaw, at least a little, the Cold War-like chill that had been characterising relations between the two countries.

Moving on from here the real debates will continue elsewhere - at the World Trade Organisation and at the UN negotiations on climate change in Bali in December.

Angela Merkel may well see this summit as a mission accomplished.

Germany's diplomatic standing has been enhanced as has her own international profile.