As any fan of Oscar Wilde will tell you – to lose one set of laptops may be regarded as a misfortune. To lose three in a year seems like carelessness.

Those were no doubt the sentiments of managers at Californian bank Wells Fargo who yesterday had to admit that thieves had stolen a stack of laptops stuffed with highly sensitive customer information from the office of a business partner.

It was an embarrassing admission for any financial institution to make. What made it worse for Wells Fargo was that it followed an almost identical announcement in March when an employee's company computer was stolen from the boot of a car in St Louis.

Five months before that, thieves broke into the Concord, California, office of an analyst employed by Wells Fargo and stole yet another computer packed with confidential data.

"There is no indication that the stolen information has been misused," said Wells Fargo spokeswoman Janis Smith, in an effort to make both staff and customers feel a little better.

In the old days – way back in the 1980s – corporate criminals had to put a bit of effort into their exploits. If they wanted to get their hands on some valuable reports or documentation, they had to at least break into a safe or blackmail a manager.

But things have changed in the age of the mobile worker. Much of the information that was once safely stored in an isolated office network is now let loose to roam freely in the laptops, handheld computers and portable hard drives of travelling managers. All it takes is one forgetful executive, an opportunistic thief, and the most well-laid security plans can crumble into dust.

Wells Fargo are far from being the only unfortunates caught out in this manner, since there have been notorious instances in Britain of civil servants from the Home Office and Ministry of Defence, as well as MI5, who have had their laptops, together with the highly confidential content of their hard drives, stolen.

These stories serve to highlight the risks of the increasingly mobile nature of modern day business practices. But it is not always as simple as a stolen laptop.

Other potential vulnerabilities open up when an office chooses to rip out its cabling and let its sensitive data pass from computer to computer over a wireless local area network (WLAN). Information that can travel through the air inside an office can just as easily slip through the walls, ready to be picked up by anyone snooping around with a wireless laptop outside.

These perceived risks have been enough to make some businesses to think twice before jumping into the much-hyped world of wireless technology. A recent survey by C&C Technology found that 39 per cent of IT managers in America found that network security amounted to one of their biggest challenges.

"Wireless and mobile working can deliver enormous benefits, however there are still a lot of security concerns regarding these networks," Jason Colombo, Technical Director at C&C Technology, said last week. "To get the most out of wireless technology, businesses need to address the issues that are preventing them from moving forward."

Some sectors have been better at moving forward than others. Service and sales departments, with their armies of traveling salesmen and support staff, may have snapped up most of the latest mobile gadgets and technologies to keep in constant touch with head office.

But if you look at a sector like manufacturing, says another recent survey by research group IDC, the uptake has been less impressive. "The current adoption of mobile-centric solutions is still somewhat limited in the Western European manufacturing industry," said the survey.

"The majority of manufacturing organisations use only basic mobility functions such as accessing e-mails and, to a lesser extent, agenda scheduling and corporate directories."

That is a shame because there is a lot more that they could be doing with their mobile systems than accessing e-mail. The number of mobility-based corporate applications has been growing by the day.

There are mobile customer relationship management (CRM) applications, mobile sales force automation and inventory management systems, all designed to hone worker productivity and give a company a competitive edge.

All those applications would be available to companies, if only they had the confidence to use them and the expertise to overcome some of the related security risks.

Most of those security risks are in fact not so difficult to overcome. Most consultants recommend companies carry out constant checks on their networks, to stop employees opening up security holes by bringing in their own unprotected wireless laptops.

The latest 802.11i Wi-Fi standard takes care of the most glaring security holes on office wireless networks. And, beyond that there is the most important security rule of all: when you are out on the road with a load of sensitive data downloaded on your hard drive, always remember to lock up your laptop.

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