In the early 1770's, the author (John Howard) became aware of the distressing conditions in English jails while he was sheriff of Bedford County, England. Among the problems he encountered was the usual requirement that those in jail (often for debts) had to pay the jailer fees for provided services, even if they were acquitted. In an attempt to change this situation, the author visited many county jails in England to observe practices used in various parts of the country. He found that jailers did not receive any salaries; therefore, those incarcerated were required to pay these fees. In addition, the physical conditions in the prisons and jails were appalling. It was common for men, women, and children to be kept in the same area during the daytime. Usually there was little or no ventilation in the sleeping quarters, which were very crowded and usually without any sanitation facilities. Often, there were no openings of any kind through which daylight could penetrate the damp darkness and overwhelming stench. Consequently, many prisoners died from disease ('jail fever') or malnutrition, since food supplies were inadequate or nonexistent. In many instances debtors were treated far worse than criminals who had committed murder, robbery, or other violent acts. Many prisons had no water, some had no sewers, and due to little or no allowance for straw, bedding was nonexistent. Prison customs included newcomers having to pay other prisoners or being stripped of all belongings, gambling, and keeping the prisoners in heavy irons. Moreover, trials were held as infrequently as once a year or less. The author proposes improvements in the structure and management of prisons, examines conditions in particular English prisons, and recounts circumstances in foreigh prisons (France, Switzerland, Germany, Holland, and Belgium). Diagrams, tables, and an index are provided.