As a result of the merger of two departments at work, I am about to become my best friend's boss. We both started on the graduate trainee scheme many years ago. And now our families socialise outside of work. Do you have any advice?

With so many mergers, downsizing and restructurings taking place during this downturn, these changing relationships are happening more and more. In this potentially problematic scenario, a great deal depends on how ambitious and competitive your friend is compared with you. It will also depend on what he thinks about your abilities and competences. If he accepts that you are the better candidate for this particular job, there is unlikely to be a problem. If your colleague has trouble accepting your new role, then you have a problem.

Communicate

If your relationship is a good one, and it sounds like it is, I would suggest that you meet up and ask him what he thinks about this new situation. Listen not only to what he is saying, but what might linger beneath his words. If you pick up signs that he is concerned, even if the words don't say so (but the emotional and non-verbal aspects do), then you need to tell him what you are worried about, how important your relationship is to him and to the success of the department and the team. If your work relationship and friendship is reasonably strong, the two of you should find a resolution. The earlier you do this, the better.

Don't play boss

Some people who get promoted take on the role of “the boss”. They think that distancing themselves from their former colleagues and friends is necessary to be able to be more objective in the boss-subordinate relationship. Yet this kind of behaviour is likely to be counterproductive and to undermine work relationships.

Be yourself

Don't attempt to be someone you are not; be yourself. The most successful managers are those that are open, transparent, genuine and supportive of others in their ambitions.

Spot potential problems

If your relationship with your friend is close, others might feel that you are favouring him over them, so beware of this. But do not over-compensate by not giving an important assignment or promotion to your friend on the ground that you don't want to upset the others, especially when he deserves it.

Socialising with subordinates

Whatever you do, don't give up your friendships because of your promotion. Changing a work role does not have to interfere with non-work relationships, but if you feel there are tensions, then talk about it with your friend. If you see that problems are emerging outside work, than communicate.

Your friendship should be strong enough to help you to work it through. Keeping your feelings buried and inaccessible to your friend and colleagues is the worst recipe for resolving issues. Let's get work and our work roles into perspective. As Woody Allen once said: “I don't want to achieve immortality through my work - I want to achieve it by not dying.”

Cary Cooper is Professor of Organisational Psychology and Health at Lancaster University Management School. Send your questions to businessfeatures@thetimes.co.uk

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