The world's first membership organisation dedicated to spreading happiness has been officially launched.
Action for Happiness, which claims to have 4,500 members in more than 60 countries, says it prioritises healthy relationships and meaningful activities as a means to happier living.
It has ambitions to become what it calls "a global mass movement for fundamental cultural change".
Its launch event in the City of London included tips on how to be happier.
The movement says it is based on the new science of happiness and the belief that our mood can be altered.
"Despite massive material progress, people in Britain and the US are no happier than they were 50 years ago, while there are many societies in which people are much happier than in Britain.
"Rejecting a societal focus on materialism and self-obsessed individualism, the movement instead prioritises healthy relationships with others and meaningful activities as a means to happier living," a spokesman said.
On joining the organisation, members pledge to produce more happiness and less misery.
On its website, Action for Happiness gives advice for happier living, such as do things for others; keep learning new things; be comfortable with who you are; and connect with people.
The movement was founded last year by Richard Layard, a Labour peer and professor of economics at the LSE, Geoff Mulgan, chief executive of The Young Foundation and Anthony Seldon, master of Wellington College. It has no commercial, political or religious affiliations.
Its official launch comes as some UK households are being asked, in a government survey measuring happiness, how satisfied they are with their lives.
The Office for National Statistics has added the questions to the existing nationwide Integrated Household Survey, which is currently taking place.
After becoming Conservative leader in 2005, David Cameron said gauging people's feelings was one of the "central political issues of our time".