(FORTUNE Magazine) – You're happy when you make more money, aren't you? So consider that average incomes in the West have doubled in the past 50 years. You'd expect people today to be twice as happy as people were 50 years ago. Right?

Wrong. In fact, studies show that people are precisely as happy (or as unhappy) now as they were then. This is the "paradox at the heart of our lives," writes noted British economist (and former Tony Blair advisor) Sir Richard Layard--and it spurred him to write the fascinating new book Happiness: Lessons from a New Science. In it he synthesizes a raft of recent research in the fields of psychology, sociology, and applied economics. Happiness can be measured, Layard argues, and we can make specific choices to maximize it.

Turns out that more money makes you happier only when it lifts you out of grinding poverty. Oh, yeah--getting richer than other people around you makes you feel pretty good too. But when whole societies become richer, there's no happiness boost. While Americans are the richest people in the world, the Dutch, Irish, Canadians, Danes, and Swiss are happier. Mexicans and Indonesians are about as happy as we are. And for God's sake, don't move to Ukraine.

Layard concludes that if we really wanted to be happy, we'd stop working so much. We'd get married and stay that way. We'd have kids. We'd unplug the TV. We'd help the less fortunate. And our governments would have policies to facilitate all that. (One suggestion: Income taxes on high earners should be raised, since taxation discourages work, and too much work makes us unhappy.) So the next time one of your staffers asks for a raise, just heave a sigh and reply truthfully, "It won't make you any happier." -- Elizabeth Fenner