By Lucy Kellaway

After a decade working at a senior level in a multinational, I have begun to look for new opportunities. In my last two job interviews, I have been asked if I have a Facebook account. I do not, nor do I Twitter, nor am I on LinkedIn. From what I have seen of such sites, they make my eyes glaze over in boredom. But I got the impression that my attitude towards social media was seen as a negative. Is this for real?

Do I have to sign up for social media or networking sites or be a corporate outcast?

Senior procurement director, 41

Lucy?s answer

A year ago, I would have said not only that you could safely ignore social media but that you ought to ignore it as it makes people less efficient. But now I have changed my mind. You have to join in simply because everyone else does; if you don?t, you will indeed be an outcast. That might be fine if you were a poet but it?s not fine in the world of procurement.

Reluctantly, I have signed up to Facebook, Twitter and LinkedIn because it is not fine for me to be an outcast either – in fact, it is a downright disgrace for someone who works in the media to be so hopeless about social media. However, I have yet to feel any benefit from dipping my toe in, though this failure to get anything out might be because I can?t be bothered to put much in. The only difference it makes for me is that every day I get requests from people I have never heard of to be their ?friends? or join their ?professional network?. And then, when I ignore them, I get further e-mails reminding me that I haven?t replied.

I suggest you take a selective approach. Join LinkedIn, which doesn?t take long and merely means posting your CV online. If I were you, I?d leave Twitter alone. Unless your heart is in it, it will be a great way of advertising to potential recruiters how pitifully few followers you have. As for Facebook, I am surprised that the interviewers even mentioned this – unless they wanted to check whether you are up to dodgy things in your spare time.

The truth is that most companies have not yet worked out how useful social networking is to their business. It may allow them to find out what customers think but it also allows them to waste a phenomenal amount of time wading through crud. But such is the feverish excitement, evidenced by the appetite for LinkedIn shares, that no one can afford to say they simply don?t get it.

For you to stand to one side makes it look as if you aren?t interested in the future. That is a disaster. Next time you are asked about social networks in an interview, compose your face into an expression of interest and wisdom. Tell them that you find LinkedIn enormously useful but say that, equally, you are wary of spending too much of your time on such sites as there is also a job to be done.

Your advice Invest in a profile

A good internet footprint certainly adds to your professional image. Many recruiters include the quality of internet profiles in their decision-making process and, if you don?t have one, you are positively disadvantaging yourself.

Creating and maintaining your internet profile will take up at least an hour a week but the investment is worthwhile.

Consultant, female, 50s

It?s due diligence

They are not asking you about these things because they are good things to have on your CV. They are asking because they want to know if it is worth them trawling the internet to perform a bit of extra due diligence on you.

Male, anon

Modern matters

If you do not have such accounts, it suggests a number of negatives: an unwillingness to adapt to change, to adopt new ideas and an out-of-date mentality. You are a senior procurement director. You should be keeping a LinkedIn network of contacts, who change employers, which can help reduce your company?s purchasing costs.

Male, 41

Be a refusenik

No, you do not! The very fact that you get asked the question about your web identity at interviews is proof that this is by no means a necessity to get attention from recruiters. Plus: do you really want to work for someone who doesn?t hire people without a Facebook account?

See: you don?t.

Professional, male

Nothing new

I?m not sure this is a terribly new problem. Thirty years ago, you might have bemoaned having to take up golf to get a promotion or win new business. Now it?s being online. The simple answer is to treat it like a CV. Set up your LinkedIn profile, spend an afternoon letting it make connections for you from your e-mail address book, then forget about it.

Male, anon

Where do I put alcoholism on CV?

I?m a successful federal employee trying to move in a new direction. I?m applying for jobs that I?m well qualified for and though I keep reaching the top three, I haven?t been offered any positions. The problem is that I?m a reformed alcoholic who has been sober for six years. But before that there were ugly episodes of drunkenness while at official meetings, all well known to people in my (small) field of expertise. I am proud of my sobriety and have virtually no chance of regressing. I feel I should share my history with prospective employers, but where does one enter ?reformed alcoholic? on a resume? Under ?hobbies?? Is there a way I can own up to my dark past and show that I have a bright future?

Manager, male, 40s

? The Financial Times Limited 2011