The 'talking cure' requires years of training and a talent for listening, Carol Martin-Sperry tells Leo Benedictus - just don't ask for her advice at parties

Guardian

And there is something about the tranquil professionalism of this tiny space - the fresh flowers, the abstract art on the walls, the box of tissues - that seems braced for unhappiness. Perhaps through the habit of meeting so many suffering people in this room, Martin-Sperry is just the same: calm and clearly spoken, with a soft, supportive voice that tinkles gently with the sound of moral judgments not being made. Such a haven is the last thing you would expect to find in the middle of all the frantic energy of Shepherd's Bush, west London.

So we sit, Martin-Sperry and I, in her usual working configuration: she in her chair by the door, me in front of a window that looks out on to her back garden. Next to me is an empty chair, because Martin-Sperry, though she works with "whatever comes through the door", specialises in couples. Four years ago she wrote a book on the subject called Couples and Sex.

"I'm always amazed at how many healthy people there are in their 30s who've been together a few years, have got good jobs and houses, and haven't had sex for two years," she says. "They don't have time, don't seem to be motivated, have lost desire. I find that particular problem an interesting one, and I enjoy working with it." She talks about one of the most private topics imaginable as if it were as routine as a twisted ankle. "All the problems are the same," she says simply. "They're usually about communication breakdown, expectation gaps, impossibly high standards, idealised visions of what the couple should be."

It was the acrimonious breakup of a friend's relationship more than 20 years ago that put Martin-Sperry on the road to becoming a psychotherapist, a term she uses interchangeably with "counsellor". At the time she was 40, married with a young daughter, and had recently lost interest in her career as a French translator and interpreter. "I got involved in trying to talk to each of them," she recalls, "and I said at one point, 'I don't know what I'm doing here.' So my friend said, 'Go and get some training, you'd be very good at it.' And it just kind of went click."

Martin-Sperry, who had herself benefited greatly from psychotherapy earlier in her life, immediately embarked on the six-month selection process for a place on a course with the relationship counselling service Relate. Then, after she got in, came three further years of training. "You have to want to do it," she says. "I don't think people realise what a commitment it is to train to be a therapist. You have to do your own therapy as well, which is a good thing, because you can't deal with other people's problems unless you've dealt with some of your own. Of course, you never deal with your own problems 100%, but nor do the clients who come and see me."

She practises a form of counselling known as "psychodynamic psychotherapy", which has descended directly from Freud. "To me," she says, "the theory is just absolutely obvious: if you grow up with parents who don't love you, or fight in front of you, or hit you, or drink, or are permanently unemployed, or have terrible breakdowns themselves, then during your emotional and psychological development that's what you absorb, like blotting paper. And then you don't have the tools necessary in adult life to form healthy relationships."

So it's down to our childhood every time? "That's how I work. That's classical theory." Although practitioners of other methods, she points out, might see it differently. "It's a bit like the Christian church. You've got Anglican, and you've got Catholic. You've got Presbyterian, and you've got Baptist. They don't speak to each other. And they've all got the true word of God. It's like that."

What all forms of psychotherapy share, however, is that they are entirely unregulated. The government plans to change this, but at the moment there is just a national accreditation body, the British Association for Counsellors and Psychotherapists, which supervises standards among its members but has no power over anyone else. "Which is very sad," says Martin-Sperry, "because there are a lot of cowboys out there who just put "counsellor" on the door and charge £100 a session. They have no training, but they think they can do it. It's quite dangerous."

And for a qualified, experienced and accredited psychotherapist like Martin-Sperry, however, making ends meet is far from guaranteed. To begin with, she took referrals from London Marriage Guidance, before going fully private nine years ago. Now she gets work from employers like the BBC and from word-of-mouth recommendations. She charges between £50 and £100 for each one-hour session, usually once a week. How many weeks depends on the client and the problem, but it might last for several months in total.

Martin-Sperry copes, supplementing her income with occasional television and radio appearances, and has even begun to reduce her commitments from 20 to 10 clients a week, but the insecurity of her work is permanent. "It is freelance work at its most dangerous, because sometimes a client will just disappear," she says. "I used to have a flyer and go round to GPs. You've got to be very proactive."

And of course, as if the job insecurity were not stressful enough, counselling is one of the most emotionally demanding professions a person can choose. Martin-Sperry must deal with clients who tell her they are contemplating suicide (none has yet gone through with it). As a couples specialist, she gets few clients who are seriously psychiatrically disturbed, but she did see a man who thought he might be turning into a new Yorkshire Ripper. "Of course, he wasn't." She swats the memory away. "I was quite confident he wasn't going to go out and get a prostitute and slit her throat."

Working with sufferers of post-traumatic stress disorder, Martin-Sperry has also listened to the terrible experiences of tsunami survivors, victims of sexual assault, journalists back from Iraq, and people who have been involved in car accidents. "Sometimes I think, 'Oh my God, how am I going to cope with this?'" she says. "You do listen to people's horrific stories about what has happened to them, but you just have to be very professional and cut yourself off."

Like all accredited psychotherapists, Martin-Sperry receives fortnightly "supervision" from a colleague of at least equivalent experience so she can talk about any cases that are troubling her. Not taking on too much work - Martin-Sperry believes 20 clients is a maximum - also makes a difference. "It's quite important to have a life of your own," she says, citing her family, shopping, London's cultural life and trips to France as her major distractions. "I also have very helpful colleagues who are friends," she says, "and we phone each other up and say, 'I've had a really bad day today.'"

And yet I wonder how well insulated her own life can really be. At a party, for instance, how can Martin-Sperry keep a conversation about someone's life from turning into a counselling session?

"Sorry, I'm here to enjoy myself," she butts in straight away, in a voice that is firm and uncompromising, quite unlike her usual tone. "I'm not working. If you want to talk to me professionally, here's my card. Now that I've met you socially, of course, I may not be able to take you on professionally, but I could refer you to a colleague. That's how I deal with parties." But how about people who just want to talk? "I won't let them." She won't let me either. "I think you've got to be very clear about when it is 'me' time and when it is 'professional' time."

I sense that Martin-Sperry's firmness on this point is not down to lack of sympathy, but the reverse. Her first instinct always, just as it was with her friend all those years ago, is to listen. "The other day I was on a plane," she tells me, as an example, "and I heard the person in front of me say to the cabin crew: 'Oh God, I'm really nervous about flying.' The counsellor in me immediately wanted to lean forward and say, 'I'm a counsellor. Do you want me to talk to this passenger?'" She sits up. The firmness returns. "And then the other part of me said, 'Hey, hold on, let's not even begin to go there.' So I sat back and got my newspaper out."

Curriculum vitae

Current position Psychotherapist

Qualifications Trained with Relate, post-diploma training with London Marriage Guidance, psychosexual training with LMG, BACP accredited.

Career high "Writing my book."