By Piers Scholfield
BBC News, Guatemala City
Violence against women is a major concern in Guatemala
"A paradise for organised crime," is how the Dutch ambassador recently described Guatemala.
Teunis Kamper made the comment at a news conference where he handed over a cheque for some $2.7m (£1.35m) to help fund the United Nations-backed International Commission against Impunity in Guatemala (CICIG).
Carlos Castresana is the Spanish prosecutor appointed by UN Secretary General Ban-ki Moon to head the commission and he has a big job ahead of him.
There were some 6,000 murders in Guatemala in 2007, of which only about 100 made it to court.
This near-total absence of justice can be seen largely as a hangover from Guatemala's long civil war that ended only 12 years ago.
Mr Castresana's team is already up and running and aims to have a full contingent of 150 international and Guatemalan investigators in place by July.
Carlos Castresana believes his team can make a difference
The main objective as Mr Castresana sees it is to start the process of restoring trust in institutions such as the police and judiciary.
These are beset by corruption and perceived by many to be not only involved, but often to be instrumental, in many of the killings.
One of the key tasks of the commission is to identify the existence of illegal security groups and their possible links to the state.
This is probably the most difficult part of the mandate, says Mr Castresana.
"We must work with the institutions and the institutions are obviously infiltrated, so it's very easy for us to be infiltrated at the same time," he says.
"But it is part of the challenge. We need to work with these institutions even if they are infiltrated, even if they are corrupted, and try to make them useful for the citizens."
Carlos Castresana is no stranger to high-profile cases, which have included indictments against the late Chilean leader General Augusto Pinochet and a network of Italian Mafia leaders.
In Guatemala, he has been prominent in the media, a sign of the importance the country is attaching to the CICIG.
But Mr Castresana says the commission cannot be a magic solution.
Early February saw a dozen bus drivers murdered in the capital
"Reform of the institutions is not our mandate because we have neither the personal resources nor the time," he says. "What we can do is create small units inside the bodies to be the beginning of change.
"The change that Guatemala needs can only be made by Guatemalans themselves."
The CICIG has an initial two-year mandate, which can be renewed if both sides are in favour.
"I hope we're going to take care of it so we can thank CICIG and they can go to another country, but we'll keep them as long as we need them. We're going to learn from them and hopefully in a short period of time we can do it ourselves," says Vice President Rafael Espada.
So far, Mr Castresana and his team have agreed to take on two investigations suggested by the government.
One relates to the killing of women, which is all too common in Guatemala. Mr Castresana is confident of some success here.
"If you are able to put together to work all the social, health and educational services, you can prevent most cases of gender violence," he says.
Guatemala's civil war still casts a long shadow
The second investigation comes from a direct appeal by President Alvaro Colom for help with the case of a dozen murdered bus drivers.
They were all killed in Guatemala City in the space of two days in early February.
The killings caused chaos in the sprawling capital and most people are convinced it was a deliberate attempt to destabilise the new government, which took office in January.
"They were very intelligent people with a good organisation from the military point of view. I'm not saying they're military people, but they have a well organised system which makes them very effective and difficult to get at," Mr Espada said.
Mr Castresana had no hesitation in taking on this case as it will clearly help the CICIG fulfil one of its main investigating aims.
But analysts say the commission's ability to examine these groups might already have been compromised.
Frank LaRue is a leading human rights lawyer and, as human rights commissioner in the previous government, helped set up the commission.
He says some of those who should be investigated are already too close to government.
"This government has remilitarised many of the civilian structures that should remain civilian... and they have chosen military people with questionable records in terms of corruption or connections to organised crime," he says.
"We're now living a process of remilitarisation which will make CICIG's job more difficult."
Mr Espada rejects this with a swipe at the previous government.
Impunity undermines Guatemala and its institutions, analysts say
"They didn't have any military intelligence at all so they were extremely open to a lot of errors. The military people that are working with us are very good military people with very clean records," he says.
Guatemala is not the only country facing high levels of impunity.
CICIG could serve as a model for other countries in the region, many with weak institutions, as well as post-conflict nations in Africa or the Middle East.
As for Guatemala, Mr Castresana is unsure about the immediate future.
"We're beginning almost from zero so every result we can get will be an improvement," he says.
So for now the world looks on to see what impact Carlos Castresana and his team can have.