Two years ago Jenny Stern was, by her own admission, a stressed-out, clapped-out primary teacher at an inner-city school in north London. She’d been in the profession for 17 years, and the pressure of working under a difficult headteacher while being unable to find an alternative job was taking its toll.

“Every morning, I’d wake up and in my mind I’d hear the song ‘Should I Stay or Should I Go?’. I felt that my nerves were on the point of collapse. I was gripped with the idea that there was something desperately lacking in my life.”

It took a close friend to identify what that elusive thing was that Jenny so craved. It was peace of mind. Not the easiest thing to acquire, but Jenny was desperate to try anything to find it.

Thanks to another friend’s recommendation she did, or rather she’s on the road to discovering it, through meditation.

“At first I thought ‘no way’, I’m not the navel-gazing type,” says Jenny. “But my friend assured me that all sorts of perfectly ordinary people meditate and that you don’t have to have any sort of spiritual belief. And so I took the leap. It’s a struggle, but each time I do it I’m amazed at how much better I feel afterwards, and how that feeling lasts for longer and longer.

“It’s like I’ve suddenly put on a pair of glasses that allows me to see things more clearly, and at the same time it makes me feel calmer and more focused. I’m more able to do and think about one thing at a time and to be fully present in that moment.”

There are many ways of defining meditation. Paramananda, a meditation teacher, author and chair of the San Francisco Buddhist Centre, calls it “the art of getting to know one’s own mind and learning to encourage what is best in us”.

However you describe it - and definitions do tend to be on the ethereal side - meditation has been used to bring inner peace to people suffering from dukkha (a Buddhist term for spiritual uneasiness) for thousands of years. And there are as many techniques as there are definitions.

All of the major religions of the world - Islam, Christianity, Judaism, Hinduism and Buddhism - use forms of meditation, but you don’t have to be a card-carrying believer to meditate. Agnostics and atheists do it too.

The techniques used by Jenny and the North London Buddhist Centre, where she learned meditation, are Western adaptations of the Theravadin tradition practised by Buddhists in South-east Asia. Meditation techniques fall into two main categories, samatha (tranquillity) and vipassana (insight). These groups embrace a range of methods, with names that might jar with cynics:

“Loving Kindness”, for example, is supposed to induce a transformation of emotions, and “Mindfulness of Breathing” aims to enhance awareness and inner peace.

With Loving Kindness, you picture a person you love and expand the feeling you have for them to others. Transcendental meditation, as popularised during the Sixties by the Maharishi Mahesh Yogi, guru to the Beatles, uses mantras or a repeated word or sound as the vehicle for arriving at a state of consciousness that transcends our sense of self. Walking Meditation is what it sounds like: you walk slowly up and down a flat piece of ground or in a circle to focus the mind.

All you need is the ability to breathe and visualise. It sounds easy but, as I know after my first attempt in a meditation class, it isn’t. After less than six minutes of concentrating deeply on my breathing and counting to 10 over and over again, I fell asleep and rolled off my mat with an embarrassing thump.

Whatever the technique, the goal is the same: to achieve, through concentration on a single activity or object, a heightened awareness. That awareness brings with it a clarity and positive vision. It has measurable spin-offs, too. Numerous studies have shown meditation can have dramatic physiological effects, including better memory retention, a reduction in blood pressure, and an improvement in conditions such as asthma and diabetes. These changes occur as a result of the stimulation of alpha waves in the brain, which are associated with calmness. During meditation, the level of alpha waves is higher than during sleep.

Catherine Kindersley, a special needs teacher in London, has found professional benefits in meditation, which she’s been practising twice a day for the past six years. “When I meditate, I find a stable and still platform in my mind that allows me to see beyond the superficial to the real,” she says. “So when I’m dealing with children or other teachers or parents, I’m able to respond appropriately to a situation rather than reacting emotionally.”

She feels meditation has also enhanced her classroom management style. “To be a good teacher and to be able to inspire pupils, you need to be in control of yourself in a natural way. I’m sure the quality of my relationship with my class has improved, because I’m working from a point within myself rather than an external point.”

Like all the worthwhile things in life, it takes practice and time to get to the sanctuary within your mind that gives you that focused inner peace. But Vishnapani, a teacher at the north London Buddhist Centre who started meditating when he was 14, says it’s not the sort of thing you should worry about perfecting straight away. Twenty years on he finds that “meditation is a means to an end,” he says. “It won’t solve all your problems, but it can help you see your life as less stressful. It can be a force for good.”