James Neild (1744–1814), penal reformer and philanthropist, first became interested in the welfare of prisoners after visiting a friend jailed for debt. He went on to investigate prisons across Britain, France, Flanders, and Germany, fundraising to release those incarcerated for petty debt. In 1772 he helped establish the Society for the Relief and Discharge of Persons Imprisoned for Small Debts (the Thatched House Society), which succeeded in freeing over 16,000 debtors. Published in 1812, this work records the findings of Neild's thorough survey of debtors' prisons in Britain, and also discusses those imprisoned for other minor criminal offences. Neild exposes the harsh sentences assigned to debtors and petty criminals, using this evidence to support his campaign to improve the conditions of the prisoners and to stop imprisonment for debt. His efforts to improve the conditions of prisoners eventually influenced parliamentary reforms of the penal system.