Poor households do not chiefly need small sums, Rutherford argues; they need occasional large ones. Life-cycle obligations, emergencies from illness and bereavement to fire, flood or the bulldozing of a slum, and opportunities ranging from a business to a better roof or a bribe for a secure job all demand more cash than a home can hold.

Since the poor own little to sell or pawn, the dependable route to a lump sum is to build it out of savings. Rutherford calls this basic personal financial intermediation and reduces it to three moves: saving up, borrowing against savings not yet made, and combinations of the two. The rest of the book follows from that.

He then surveys what people have devised without banks, from rotating and accumulating savings clubs to deposit collectors paid handsomely to take money away and keep it safe, and describes SafeSave, designed around tiny, irregular, daily transactions.

Known as susu, box or partner depending on the island, rotating credit associations travelled with West Indian migrants and went on working in Brooklyn. The study traces them from the post-emancipation Caribbean, where black households pooled savings for burials, weddings, school fees and small shops while later-arriving groups came to dominate commerce, to New York, where members' occupations vary and nurses are conspicuous.

The organization is deliberately informal: no constitution, no advertising beyond word of mouth, no receipts. An organizer fixes the size of the hand and the interval, recruits people known to earn steadily, and friendship stands in for collateral. Interviews with ten organizers and a questionnaire returned by users and non-users support the reading of these bodies as structural shields — adaptive devices for first-generation immigrants shut out of ordinary credit, expected to matter less to their children, and used elsewhere for house deposits and business capital.

Ardener sets out to make comparison possible across institutions that anthropologists had described piecemeal under names such as esusu and contribution club. Geertz's definition is too narrow, she argues: contributions are not always fixed, the entire fund is not always handed over, and payment is not always in cash. What is essential is regularity and rotation, a standing group of contributors paying in at set intervals into a fund that passes, entire or partly, to each of them by turns.

A survey of the literature follows, from nineteenth-century China through Japan, India, Africa and the Caribbean, with attention to how the fund is allocated: by lot, by dice, by auctioning a discount, by written tender.

She keeps returning to the point that members do not benefit equally. The first recipient owes the rest until the cycle closes; the last is owed throughout. A tentative field guide for future study closes the paper.