Last year, approximately 20,000 persons in England and Wales were imprisoned for their failure to pay a fine (1 in 5 of all prison receptions). This research shows that a small minority of fine defaulters prefer to pay off their fines through a short period of imprisonment. The research also indicates that many defaulters could not possibly pay the fine amounts levied. All but one or two of the defaulters were dependent on State benefits or were employed intermittently. The study concludes that many magistrates disregarded an offender's ability to pay when setting a fine amount. Fine enforcement is often haphazard, and recourse to imprisonment in the case of defaults is neither useful nor inevitable. There is evidence that the imprisonment of defaulters is more a response to bureaucratic pressures than a rational strategy for meeting correctional goals. A day-fine system based upon offenders' ability to pay would constitute a more reasonable fine system than the current one. Also, fine arrears are a form of debt, and formal debt counseling would be a more humane response than imprisonment. 3 tables and an 18-item select bibliography