Grameen Bank lent to the poor by making neighbors the collateral

Commercial banks in 1970s Bangladesh, as everywhere, lent against collateral: land, property, some asset the bank could seize on default. Rural villagers who owned nothing bankable were locked out entirely, forced to borrow from local moneylenders at rates that kept them permanently in debt — the standard development response was subsidized government credit programs, which mostly still required paperwork, collateral proxies, or connections poor villagers didn't have, and which suffered chronic default because the lender had no local information about who was actually creditworthy.

Muhammad Yunus, an economics professor at Chittagong University, visited Jobra village near the campus in 1976 and found women making bamboo furniture who had to borrow from traders just to buy raw bamboo, then hand over nearly all their profit to service that debt — productive, willing borrowers rendered unbankable purely by having nothing to pledge. Yunus lent $27 of his own money to 42 of them directly, then spent years persuading a state bank, Janata Bank, to extend credit to the poor with himself as guarantor, before the project was made a formal, independent bank in 1983.

Borrowers self-form groups that screen members and enforce repayment, since default cuts off the group's future credit, turning social pressure into collateral.

Group members screen out bad risks because they know each other's reputations and share future credit access.

Default by one member cuts off the whole group's future loans, giving peers a direct incentive to enforce repayment.

The community's social ties and repeated interactions provide leverage that a distant bank lacks.

The bank avoids the cost of assessing and seizing assets, making small uncollateralized loans profitable.

When you lack a resource, look for a substitute that already exists in the community—like social pressure replacing physical collateral.

By the time it won the Nobel Peace Prize in 2006, Grameen Bank had disbursed loans to over 7 million borrowers, more than 95% of them women, through over 2,100 branches, with a reported repayment rate around 98–99% — compared with roughly 40–50% at conventional Bangladeshi banks lending without this structure — and had lent a cumulative total in the billions of dollars since 1976.