In the West, a society's marker of success is economic wealth, measured in terms of GDP (gross domestic product). In developing countries, growth in GDP usually equates to social progress - access to better healthcare, food and the other basic needs of life.

But since the 1950s, what we have seen in developed countries is that, even though we have become three or four times wealthier, there has been no increase in life satisfaction.

Many economists now say we need a broader measure of success, and should include things that really matter to us, such as levels of trust, mental health, community spirit and family stability. As Bobby Kennedy said decades ago, GDP "measures everything in short, except that which makes life worthwhile".

It is a similar story on the personal level. We live in a culture where we tend to define individual success in terms of material wealth. It is thought that one of the reasons we are richer but no happier is that we tend to care more about our comparative wealth - in other words, if we earn more, but so does everyone else, we don't feel any happier, so we struggled to be fulfilled.

The relatively new field of positive psychology has been researching what really makes people happy, and the findings from all over the world can broadly be grouped into three themes.

First, a sense of acceptance of who we are - the extent to which we are comfortable within our own skin and have a positive, but realistic, attitude to our lives. Second, positive relationships of all kinds - with our partners, families, communities and colleagues. And third, having a sense of meaning and purpose in life - we want to help others and make a contribution.

The research findings are very empowering because they remind us that, once you have the basics in life, these other factors are far more important than wealth and possessions.

However, there is evidence that we are quite bad at knowing what makes us happy. We are bombarded by media and marketing messages that success is about fame or wealth, although this is often the route to misery.

I believe that, deep down, people know what is really important to them - if you asked them what they really cared about they wouldn't say "a bigger car". But this needs more conscious thought, and we should try to build our lives around that.

It comes down to trade-offs. Some people think the best thing they can do for their family is be there as much as possible; some think it is to work long hours and provide for them. There is no one right answer.

The key is to decide what makes us feel most fulfilled. We need to be honest with ourselves and resist what peer groups and society tell us is the right answer.

Mark Williamson is director of Action for Happiness, an online network whose members pledge to commit themselves to producing more happiness in the world and less misery, applying this in their private lives, at work and in the community.

This article was previously published in the January 2011 edition of John Lewis Edition.