Rewards can be great, particularly when fringe benefits are taken into account, often doubling the take-home wage of those involved.
Engineers, for instance, used to a UK salary of pounds 35,000 to pounds 40,000, can boost this to a package worth pounds 70,000 to pounds 80,000. In the best cases this can be for six months' work in the year and be tax free.
"They are like modern-day mercenaries," said Paul O'Bryan of Premier Personnel in Leatherhead, Surrey, who has placed people in Somalia, Croatia and Papua New Guinea.
"Let's face it, if you are going to work somewhere really, really nasty then you are going to want to get paid for it."
Even advice from the Foreign Office not to visit a particular country seems to be little deterrent for seasoned expatriate workers.
"Some people will get a bit scared and walk away from a contract, but the real old hands don't seem to be too bothered," said Patricia Holgate, marketing manager of Commission Services, in Kingston upon Thames, Surrey. "Some would say that trouble in these places tends to blow over fairly quickly. Others would say, `This is a hardship area, so how much more money will you pay me?'"
Her company certainly has an exotic client-base - currently employing people in the Democratic Republic of the Congo and southern Sudan, both of which are on the same Foreign Office list as Chechnya as places where the Government "advises against all travel". A contract has recently been completed in Algeria and people are being sought for a new construction project in Kashmir, both of which are on the list and have fearsome reputations for violence and kidnapping.
One man spent three weeks under siege after being caught in Iraq at the beginning of the Gulf War, but remains undeterred and has undertaken a number of unpleasant assignments since, Ms Holgate said.
As well as salary weighting (known as "uplift") of 50 per cent to 70 per cent, expatriates would have all accommodation paid for, and be given a generous daily living allowance, travel expenses, training and holidays, which might amount to as much as one month on and one month off. If they are out of the country for a full tax year, this would all be tax-free.
"People are made aware on a daily basis of how to keep themselves sweet with the locals and of any developments in the situation there," Ms Holgate said.
"If anybody's life was in danger they would be brought back straight away. But at the end of the day it's entirely up to them to look after themselves when they are out there."Reuse content