The idea sounds simple: your mobile phone is your office. Pick up a tan as you work on the beach. Become the envy of your friends as you compile a PowerPoint presentation without leaving your bed. Amaze colleagues by being in three places simultaneously. For a new generation of mobile phone technology - otherwise known by its technical name, 'General Packet Radio Services', also nicknamed 2.5G - now allows users to connect to their office's IT systems from outside for the first time: the era of the wireless worker has well and truly arrived.

But the reality of this brave new world is, actually, a little more complicated. While the idea of using mobile handsets to collect emails or connect to corporate intranet systems has captured people's imaginations, company IT managers need to do their homework before betting their budgets on the technology.

This is because integrating a workforce to a business's 'back office' - servers and infrastructure that power a business's data services - involves making some crucial choices, choices which will have major ramifications on whether the new technology will help boost a company's productivity, the only reason it should be employed in the first place.

The first thing an IT manager needs to work out is exactly what they want from integrating a company's workforce with its back office systems. While the idea of issuing all staff with the latest technology might win managers the love of their colleagues, they could be spending too much on stuff they don't need. Much will also depend on budgets and a company's size.

Fortunately, the big network operators have developed a number of models to help befuddled companies work out what they need. These range from templates of the smallest company, up to the big corporate clients with workforces of more than 2,000.

'We'll start by asking what problem is the consumer trying to solve and what the value proposition is,' says Alastair MacLeod, customer development director with Orange's Business Solutions.

As ever, companies are focused on the bottom line - what return they will get on their investment. 'They're keen to find out the predictability of costs, otherwise it's hard to build a business case,' adds MacLeod.

One of the key issues in deciding which integration approach to opt for is how much data a mobile workforce will need to download. The new generation of handsets might make their predecessors look prehistoric, but in terms of data processing speeds and capability they are still a long way behind a conventional laptop, which also has the added benefits of coming with a good-sized screen and keyboard.

'It really depends on what you want the service to do. If you've got a workforce that needs to download big payloads you're better off using laptops with data cards,' says Paul Stonadge, corporate product executive with Vodafone. The cards work by allowing the user to connect a device to a Local Area Network, a fixed wireless network which can be accessed when the user is in close proximity. T-Mobile, for example, has struck a deal with Starbucks coffee shops to put LANs in a number of its outlets.

Data cards create a range of possibilities, but they may not be suitable for everyone. For those employees who need to pick up their corporate emails while on the move, wherever they are, a system which integrates their mobile phone with a company's back office will be far more useful.

But potential users should be aware that the industry is divided on this issue. The likes of Vodafone and O2 currently favour issuing clients with BlackBerry personal digital assistants (PDAs) rather than their own branded mobile phone handsets. The PDAs have become hugely popular with some users, many of whom are drawn to their ease of operation.

Sir Martin Sorrell, chairman of advertising giant WPP, for example, is a convert. 'The BlackBerry solution is good for someone like me who's not that technical but needs easy and timely access to email and calender information. You only need the most basic skills to be able to use it and it means I've got instant email and can respond wherever I am,' he said.

Sorrell chiefly appreciates not having to lug a chunky PC around with him when he's moving around his business empire. He can roam on Vodafone's GPRS network, allowing him to pick up his emails at any time. 'It means there are no logjams when you come back into the office. As an example, over Christmas last year I was trying to play golf and often had to check my email before we started the next hole.'

BlackBerry devices, though, need to be integrated with BlackBerry soft ware and servers if they are to work properly. Engineers will have to install the kit - which should take only a matter of hours. Other mobile phone operators, though, led by Orange, have been reluctant to push the BlackBerry case. 'We're device agnostic,' MacLeod said. 'We find we get people who love their PalmPilots and others who've had an iPaq for years and couldn't do without it.'

Whether both sides will remain so firmly entrenched on the matter is open to question. Orange hasn't categorically ruled out introducing a BlackBerry product to its suite of solutions and the other operators are also looking at how to broaden their range of offerings.

Ultimately it is which network and which device works best for a particular business that should win the argument. IT managers should focus on what is on offer from the solution providers - those companies that create the applications to work with particular devices and networks - and which can give businesses a cutting edge before making their final decision.

Theoretically, these applications should sit as comfortably on one network or mobile device as any other - thanks to agreed industry wide standards. But MacLeod offers a piece of advice: 'Standards aren't as standard as they might seem. The reality is different - networks work better with certain components than others.'