Kevin Keegan has surprised everyone by returning to his old job as Newcastle United manager. However, it's a situation that's becoming more and more common as online news resources and even social networking sites make it ever easier to find out where your old employees have ended up.

Once you've found them, however, it's rarely just a case of getting on the phone and inviting them back into the fold. You need to be offering them something that they aren't getting at their current workplace, and mere nostalgia just won't cut it. Employers should also ask themselves their reasons for bringing back a former worker — are they really the answer to your recruitment prayers, or has time given you a pair of rose-tinted spectacles?

Establish reasons for leaving
It's important to understand why somebody left in the first place to make sure that the same won't happen again. If the reason was a step up into a higher position or a job with more pay, you need to make sure that you have a generous enough offer and plenty of opportunities to progress.

If, however, there was a clash of personalities or the culture wasn't right, you have to be absolutely sure that things have changed at your company; otherwise, the employee is likely to want to leave again, if they even decide to rejoin in the first place.

Don't burn your bridges
If you think you might want somebody back in the future, make it 100% clear to them and to others that the door will remain open. It's then a case of keeping in touch — not as friends, but as part of the professional network. Take an interest in what they're up to and congratulate them on any career successes without coming across as bitter.

As well as keeping in touch with the ex-employee, it's worth taking a temperature check on the market to see how they're perceived, particularly if you are seriously considering bringing them back on board. It might not be appropriate to go to their new employer, but it's a good idea to get opinions from key clients or customers.

Think about your current team
If you have decided to re-recruit a former member of staff, consider how it will be received internally. It's critical that you explain the benefits and make sure it won't have a negative impact elsewhere.

At the same time, don't make them out to be some sort of 'messiah' — they will be embarrassed by the hype and are bound to end up disappointing — then you will be the one who is left with egg on your face. Similarly, make sure the person returning has left their pride and their ego at the door. They may need to work hard to explain why they have come back and, if they have returned at a higher level, what they have done to justify it.

Provide an incentive
As well as addressing the issues surrounding why the employee left in the first place, it's vital that you have some sort of incentive to draw them back in. It could be an attractive benefits package, a significant pay increase or a more senior position. Whatever it is, your offer has to outshine what they're currently getting and what they could get elsewhere — don't just appeal to the 'good old days'.

Make sure it's a step forward
You have to make sure the ex-employee will be an asset to the company. Have they learnt new skills or new markets, or have they developed as a recruiter or a manager? If they have, someone has done your training for you and you can only benefit. If not, it's probably not worth bothering.

Returning to a former employer shouldn't be seen as taboo on either side of the equation, but it is imperative that neither has to take a step backwards.

Mark Gardiner Regional manager at recruitment firm Stark Brooks Associates

Key points:

• Discover why staff left in the first place

• Keep in touch with staff who leave

• Check they will fit in with the existing team

• Offer them an incentive to return

• Only bring people back do it if it's good for both parties — not just for old times' sake