Karl is very good at Scrabble. When this 26-year-old is playing the word-game on the internet, he's unstoppable, laying down the letters as fast as he can, flicking Fs and Xs and Vs onto the stumps and stubs of his opponents' words, studying the dictionary for obscurities, calculating his odds like a card-sharp.

It's good that Karl has a talent for tiles, because he also has depression and social phobia. He is recovering from drug and alcohol addictions, and rarely leaves his flat. It is not often that he feels like a success.

But there's a growing school of thought in mental health that says Scrabble might be the key to Karl's recovery.

The idea is that everyone has hidden mental strengths, even if they are buried beneath a lifetime of unhappiness or abuse. It will probably be revealed only in some apparently insignificant habit - caring for a pet, doing crosswords, keeping fit - but it is an indication that this person already knows how to think positively and is in fact already doing it, albeit without knowing.

Karl might feel he is useless and defeated, but Scrabble shows that his brain is actually resourceful, creative, thoughtful, intelligent - all skills which could help him overcome depression and anxiety. He is seeking social engagement by approaching other net Scrabblers and challenging them. He knows how to overcome obstacles - dumping all his letters and starting over when he gets stuck.

The trick is getting Karl to see inside his own mind, say American psychologists Christine Padesky and Kathleen Mooney, two of the world's leading cognitive therapists who are in New Zealand to teach their methods of questioning clients to discover their inbuilt "resilience" to depression.

After decades of research and practice with depressed clients, they want to shift the focus from illness to wellness - to promote the idea that every human being can teach themselves how to cope with life's challenges.

"You don't necessarily need medication, you don't necessarily need therapy," says Padesky, a tall, humorous woman with sleek brown hair.

"Therapy and medication can certainly help, but if you don't have access to those things, or you want to try and do it on your own, there are clear steps you can take that we know from research will usually help people feel better.

"A lot of people don't realise that. They think if they are depressed they're just stuck with it.

"Sometimes, when people are really depressed and feeling very negative about themselves, it's hard to see how you figure out your own strengths, and that's where psychotherapy can be helpful. But once people learn this, they don't need the therapist. We're in the business of putting ourselves out of business, and that should always be a therapist's goal," Padesky says.

The idea is, in part, an acknowledgment that therapy for depressed people often focuses only on the negative, sad parts of their lives - like Karl, a real-life client whose case was discussed by one of the 200 therapists at a workshop on resilience in Auckland this week, organised by the New Zealand College of Clinical Psychologists.

By helping people develop the skills to resist depression, Mooney hopes to address one of the major issues in depression research: Why does the condition recur so often, even after clients think they are well?

"It's fine to bounce back from a bout of depression as long as what you're bouncing back to is a positive state of mind," says Mooney, a diminutive livewire with a broad smile.

"Our task as therapists is to search for these skills in our clients, to help them transfer the everyday skills they have into their own mental health."

Depression is sometimes described as the canary in the coalmine of society; an early warning that things are not going well.

In New Zealand, most estimates are that depression affects about 10 per cent of men and up to 25 per cent of women - but the Mental Health Foundation says most sufferers are never diagnosed or adequately treated.

Auckland businessman John Schroeder - a thoughtful, enthusiastic 55-year-old - first became depressed nearly 30 years ago, when he was suddenly promoted to his first management job in a female-dominated workplace.

He knew his female colleagues felt he got the job because he was a man. "I had some sympathy, because I actually strongly suspected that it was in fact true," laughs Schroeder, whose GP referred him to a cognitive therapist.

Through the therapist's questions, Schroeder came to realise he had a "twisted sense of reality ... you develop a distorted view of the world. I thought because there might have been some gender bias I was unworthy."

He learned to practise daily relaxation, to remember that he is only a small player in other people's lives (even when they are angry with him) and that he must accept circumstances rather than despairing over them.

"If something has happened, even if it is entirely your fault, it has occurred. And the only thing to do is deal with it; put it right in whatever way you can."

In New Zealand, clients such as Schroeder must pay fees of as much as $160 a session to see a practitioner, unless they are eligible for low-income support from Winz or are suffering the results of an accident, in which case ACC pays. That irritates Otago University professor Peter Joyce, head of the mental health clinical research unit, who believes New Zealand needs a public health system where therapy and visits to psychiatrists are free.

"Therapy is only readily available if you have money and that's a major issue," Joyce says.

"Maybe I'm an idealist, but I think this is what our public health system should provide. Some people with depression do better with different types of therapy, and a decent service needs to provide options."

The resilience techniques advocated by Padesky and Mooney are not revolutionary but part of a global focus among mental health workers on the positive side of mental illness - mental health. Over the past five years much international research has examined the idea that some people have an innate resilience to depression, that it might be possible to foster mental health by teaching those techniques, particularly to adolescents.

Researchers led by Dr Sally Merry, of the University of Auckland, discovered that high-school students showed a long-term decrease in depressive symptoms after participating in "resourceful adolescent" classes, where they were taught techniques such as problem-solving, thinking positively, relaxing and actively seeking the help of others.

"I don't think we've got it all crystallised perfectly just yet, but there is really something in this idea of preventing depression," says Merry, who is also analysing data on depression-prevention programmes internationally.

Auckland psychologist Gwendoline Smith says New Zealand therapists are faced with a very different challenge to those working in America, where acceptance of the effectiveness of antidepressants is widespread.

Some New Zealand clients refuse to take antidepressants despite evidence that they often help with major depression, says Smith, which makes it difficult to focus on positive thinking.

"For a New Zealand clinician, we've got to get people bloody well up off the floor and get them out of bed first. We're in a very different place to American clinicians. But having said that, resilience research is increasingly of interest here and around the world.

"Is resilience genetic or can it be learned? That's the big question for clinicians. Can we teach people to do this?"

Marijke Batenburg, a psychologist and one of the college's spokespeople, says many experienced practitioners are already - and perhaps unconsciously - using the techniques of resilience, as well as other positively focused evolutions in psychology like one of her own specialties, "mindfulness", where clients are taught to step back from their moods and let them pass rather than allowing themselves to be swept along.

As a therapist "you can't sit in the realm of problems all the time - that's a constant battlefield, and sometimes that internal battlefield is what has brought the client to therapy in the first place", she says.

Christine Padesky, when a young researcher, wanted to study the amazing ability of some people to cope with hardship and sadness but was firmly told by teachers that serious mental-health research focused on pathology, on depression itself, rather than the people who avoided it.

It is only now as a senior practitioner that she feels she has "proven myself enough to go back to what interests me, which is how do people function well? I'm interested in learning the lessons of people who cope, and creating a very simple model to help people right themselves and get back on their feet".

Like Padesky, Kathleen Mooney has worked closely with Aaron Beck, the American psychologist who created cognitive therapy in the 1950s, and says Beck is enthusiastic about the worldwide research on resilience.

Mooney says: "The idea is not that life can be risk-free. There are a lot of risks in life, and we can't eliminate a lot of those, but if we can help children, and adolescents in particular, to get more of the protective factors of resilience, that will stand them very well. It doesn't mean you're not going to be upset, angry, or sad, but with resilience you won't get stuck in the trough."

Depression

What is it?
More than just sadness, clinical depression is a prolonged low mood involving symptoms that include exhaustion, feelings of worthlessness, listlessness, agitation, thoughts about hopelessness and death, and problems with sleep and appetite.

How many people does it affect?
 In New Zealand, estimates range up to 1 in 10 men and 1 in 4 women. Between the ages of 15 and 18, rates of depression leap. The most commonly affected group is aged 25 to 45. More than 200,000 New Zealanders use some kind of antidepressant medication every year.

How can it be treated?
Usually, patients are treated with a combination of medication and therapy.

What is cognitive therapy?
It involves examining a client's thought processes and helping them learn how to control their own moods by getting out of negative thinking habits.