Chrystia Freeland, Penguin Press, 330 pages, $27.95

An Egyptian telecom magnate, discussing how much of a fortune is enough, figures on $1 billion: "That's my number for the minimum," he says in this exploration of the super-rich.

Moving from Davos to Martha's Vineyard as she stalks her subjects in their luxurious lairs, Chrystia Freeland observes the subtly malign effects great wealth can have.

She finds a general disregard for the sufferings of the middle class and an obsession with not paying more taxes. In the United States, where finance has played a disproportionate role in producing mega-wealth, Freeland's subjects tend to blame government or the middle class for the country's economic woes, not the recklessness of bankers.

To people whose every whim is instantly satisfied, the slightest inconvenience can provoke outrage. In one case, she reports cadging a ride with a financier. As they struggled to find his car and driver at Heathrow Airport, he "fumed about the wait, berating himself for breaking with his usual practice" of having his assistant on call at all hours.

Freeland is acutely conscious of the way inequality and plutocracy have risen in tandem, even as growth in the developing world has helped shrink inequality between nations. Of course, the rise of a new Asian middle class is small comfort to the ailing U.S. middle class.

Freeland is an insightful and indefatigable reporter, but she doesn't present a strong central argument about how, or whether, to counteract the trends she describes. While often informative, the book is poorly organized, with thematic chapters that are hard to tell apart and countless anecdotes that go on too long.

Freeland concludes by reminding us of Venice, which 700 years ago made itself a wealthy imperial power. The city fell into decline when its own plutocrats tried to cement their advantages, thereby stifling the openness that accounted for the society's dynamism.

Today, of course, Venice is sinking. Freeland's book will make people wonder if we are, too.