It's all about balance, the experts say. Too much money, too much achievement, too much hedonistic pleasure, too many possessions can all make us unhappy. Somewhere in the middle is just fine.
Dunedin psychologist Chris Skellett, author of the new book When Happiness Is Not Enough, reckons Kiwis aren't too bad at it.
You'd think that someone who deals with people's misery on a daily basis would have a more jaundiced view, yet Skellett believes New Zealanders are a happy bunch by world standards.
"We are balanced and overall we are happy," says Skellett, who has spent more than 30 years listening to clients' woes in his psychology practice. "New Zealand is a cruisy country. It is so easy to relax and enjoy life ... and it is a wonderful country of opportunity."
But lurking among us are "the worried well". They're the people who don't realise how happy they are or, more importantly, how to take control of their happiness, says Skellett.
"I say, listen to your heart. Is it soaring with joy and beating with pride? Then you are happy." Skellett's theory, which is based on years of studying patients and clients, is that being happy is a matter of finding a balance between indulgent pleasures and achievement-oriented satisfaction. In other words, too much of a good thing will lead to unhappiness.
On one side are pleasure and indulgences, pursuits which are transient and often quickly gone. On the other side is achievement, which gives us a feeling of satisfaction, pride, courage, enthusiasm, motivation and drive.
But too much focus on achievement, Skellett warns, creates its own psychological problems, including stress, burnout and obsessive problems. The antidote is to balance achievement with pleasure.
"Essentially, these people need to stop and smell the roses," says Skellett.
Conversely, although pleasure is important to achieve happiness, a life of self-indulgence isn't the answer either.
Holidaymakers who go to the Gold Coast to compete in a half-marathon or other event will be achievement-focused and those who go to the same location to kick back and relax are pleasure-oriented.
But the achievers might actually be happier if they lay on the beach and the hedonist might get more satisfaction from a goal-focused holiday.
Skellett regularly sees couples in his consulting rooms who have achieved their material goals, but are still not happy. People who are overly achievement focused in particular sometimes have difficulties moving to the next phase, he says. And a couple may have very different views on how that next phase will shape up.
In addition, he says, people need to take ownership of their own happiness and other emotions such as anger.
"If you rely on someone else owning your happiness or anger, you are not in control of your own life."
At Auckland University's Business School, Dr Ross McDonald studies a wider view of happiness. McDonald, a senior lecturer in management and international business, works with the Government of Bhutan to help it maximise Gross National Happiness (GNH), which it rates as more important than economic measures such as Gross Domestic Product (GDP).
At the core of what the Bhutanese call "GNH thinking" is the belief that the global system has become aim-lessly destructive because the economy is only a means to an end, and not an end in itself.
"For the Bhutanese, economic activity is legitimate only when it contributes to spreading harmony and happiness," McDonald says.
"In a GDP-dominated world the personal happiness we seek is fleeting, disconnected and immediate. In a GNH world, true happiness is stable, connected and accomplished."
These aren't woolly ideas from an obscure country. The British Government has dedicated £2 million ($4 million) to a plan to measure people's well-being in that country.
Happiness is also a subject that concerns the New Zealand Government and in particular the Treasury. As well as its economic, fiscal and regulator roles, Treasury assesses areas such as health, education and employment to determine how Government- improved economic performance enhances living standards, which can't be measured by GDP alone.
The good news is, says Treasury senior analyst Ben Gleisner, when it comes to happiness, the New Zealand Government gets good "bang for its buck".
"If you look at developed countries we have good happiness for the level of income the country produces."
According to the Gallup World Poll last year, New Zealanders' rating of their satisfaction with life is high relative to other countries such as the UK and Australia with higher GDP per capita.
There is a point, says Gleisner, where additional money has diminishing returns in terms of happiness.
"The last extra bit [of income] you spend on discretionary items doesn't add as much happiness as the first lot of money you spend." Transferring income to the people at the bottom would help maximise happiness, he says. Enabling a poorer person to buy his or her first car, for example, would add more to the country's overall happiness quotient than allowing a richer family to buy its third car.
Gleisner quotes British economist Richard Layard who highlights five factors that contribute to a nation's happiness. They are: family relationships, financial situation, work, community/friends and health.
AUT lecturer in psychology Charmaine Bright is researching how to help children and teens become happier.
Like Skellett, Bright favours a balance between "intrinsic motivation" (pleasure) and "extrinsic motivation" (reward for achievement). Parents who focus on achievement - such as "you can get X if you achieve Y" are setting a very different scene psychologically for children to those who simply love their children for being themselves.
"If children are more intrinsically motivated life satisfaction will be increased," says Bright. "If you are only doing it for the reward you will be less satisfied."
She cites the example of mathematics, which many children are not keen on. Simply pushing children to achieve mathematics for extrinsic reward is less likely to make them happy than getting the child to reflect on how they can enjoy maths.
"It's not saying you shouldn't promote achievement orientation for your children, it is more about making sure they are doing things for the pleasure of it, not pushing them into it."
Concentrating on what children (and adults) do well, says Bright, is important rather than focusing on what has gone badly. "Negative emotions can spiral downwards and positive emotions spiral upwards. It is about looking at the positives, taking what is good, and focusing on it."
When Happiness Is Not Enough
by Chris Skellett
$34.99, Exisle Publishing.