The United States guarantees its citizens can pursue it. Norwegians apparently have more of it than others.
Happiness has become the business of governments, but a new Australian National University study says differences within countries, and not between them, have a greater influence on well-being.
Annual world rankings of happiness are routinely dominated by Scandinavian nations, but they may be less reliable than they appear, according to study author Richard Burns.
His report, published in the Journal of Happiness Studies, found differences within nations in wealth, and trust in the political and legal system, had a greater influence on people's happiness than disparities between countries on the same measures.
Whether people could live comfortably on their wage, and not national GDP or GDP per capita, were more important deciders for someone's well-being.
Happiness did not vary much between nations included in the multi-national study, which looked at survey results from 23 European nations ranging in national wealth from Ireland (US$72,600 GDP per capita) to Ukraine (US$8700).
"Whether citizens in different nations are living with a sense of purpose, vitality and engagement, or of belonging to a community - strong indicators of people's happiness - is really unrelated to the nation in which they live," Dr Burns said.
His report measured happiness using survey results that gauged how people felt psychologically - including their emotions and self-esteem - and their sense of purpose, vitality, autonomy and engagement.
Differences within countries in net family income were most strongly related to well-being across most of the measures.
The results challenged the idea behind the annual World Happiness Report, which was based on narrower definitions of well-being, he said.
Nation-level differences still needed examining, as inequalities within countries could be addressed through their political structure and public policy, the study found.
In the World Happiness Report 2017, Norway ranked highly on the main factors found to contribute to happiness: caring, freedom, generosity, honesty, health, income and good governance.
Norway moved up four places in the last rankings to knock Denmark off the top spot, and Iceland and Switzerland rounded out the top four. Australia tied with New Zealand, Canada, the Netherlands and Sweden for ninth place.
"There's always a degree of scepticism about what they are actually measuring," Dr Burns said.
"These are really not very useful league tables."
Dr Burns said the study showed governments could improve their citizens' well-being more by reducing wealth inequality, and improving the ratio between living wage and cost-of-living, rather than trying to match other nations' social and economic policy.