Who isn't looking for that holy grail that is the secret to a happy life?
It could be all down to genes, where you live, what you do or how much money you have, depending on the research you read. But now, scientists have identified a new explanation for our joy (or not) in life.
Our attachment to groups and how much we feel a belonging with them is the latest cause identified for our feelings of happiness.
The study, appropriately enough published in the Journal of Happiness Studies by researchers at Nottingham Trent University, looked at nearly 4,000 people and which groups they identified with, such as family, local community or sports group.
Those who felt part of a group were found to be happier than those who weren't, while those who were a part of more than one were happier than those who were part of just a single group. For each additional group, the researchers found happiness levels increased by nine per cent. This was the case even when they took into account several other factors such as gender age and nationality.
"Our findings suggest that thinking more about one's group life could have significant benefits for an overall sense of wellbeing," said Dr Juliet Wakefield, a psychologist at Nottingham Trent University.
"It's important to note that identifying with a group isn't the same as membership, though. You can be a member of a group with which you feel no connection at all. It's that subjective sense of belonging that's crucial for happiness."
Feeling part of a group provides a stronger sense of purpose and security as well as social support during tough times and could explain the happier nature of people who feel belonging, they suggest.