The meditation technique aimed at focusing the mind on the present moment is an effective treatment for depression, according to a new report. So what is mindfulness and how do you do it?

A report published this week analysing data from 47 clinical trials involving 3,000 participants suggests that mindfulness, a meditation technique aimed at focusing the mind on the present moment, produces measurable improvements of up to 20% in symptoms of anxiety and depression compared to people who practise another activity, and can also help alleviate feelings of stress and enhance quality of life.

So what is mindfulness, and how does it work? Unlike mantra meditation, which involves focusing concentration on a particular word or sound, mindfulness aims to achieve a relaxed, non-judgmental awareness of your thoughts, feelings and sensations; what Mark Williams, professor of clinical psychology at the Oxford Mindfulness Centre, part of Oxford University's department of psychiatry, calls a "direct knowing of what is going on inside and outside ourselves, moment by moment".

Buddhist monks have been practising a similar technique for 2,500 years, but western medicine caught on in the late 1970s when a US medical professor, Jon Kabat-Zinn, began successfully treating patients with chronic pain using a secular programme he called Mindfulness-Based Stress Reduction. In 2002, Williams and colleagues from Cambridge and Toronto universities devised Mindfulness-Based Cognitive Therapy for Depression, aimed at helping prevent the relapse of depression.

Clinical trials have since shown that MBCT is as effective as antidepressants, and in patients with multiple episodes of depression can reduce the recurrence rate by 40-50% compared with usual care. Nice, the UK's National Institute for Health and Clinical Excellence, approved MBCT for the management of depression in 2004, meaning the therapy is available on the NHS.

In recent years, organisations as varied as the US Army, Google, Transport for London, PWC and the Home Office have started offering mindfulness training for employees; increasing numbers of schools are incorporating it into the curriculum for 13- and 14-year-olds. In everyday life, mindfulness is about learning to direct our attention to our experience as it unfolds, rather than "living in our heads". Too often, proponents argue, the pace and stress of modern living leave us caught up in a stream of thoughts and feelings, trapped in past problems or overwhelmed by future anxieties. The theory is that by connecting with the present moment, calmly observing our thoughts, feelings and sensations so as to become more directly aware of them, mindfulness practitioners become, essentially, better able to manage them.

"It lets us stand back from our thoughts, and start to see their patterns," Williams says in an interview for the NHS. "Gradually we can train ourselves to notice when our thoughts are taking over, and realise that thoughts are simply 'mental events' that do not have to control us. Most of us have issues we find hard to let go and mindfulness can help us deal with them more productively."So how do you do it? First, by becoming more aware of the world around you: switching off the auto-pilot, noticing and watching your thoughts and feelings, waking up to the physical sensations of things. Second, most teachers recommend a set daily period of more formal mindfulness practice. The techniques sound simple enough: sitting in a quiet place, deep-belly breathing, paying attention to your body, training the mind to observe, focus and filter. In fact, setting aside 15 minutes a day is often tough, and stopping the mind wandering even tougher. There are, needless to say, a myriad courses available to help, including online and even apps. And most of those who who do it, swear by it.