Four courts in England participated in an experiment in imposing and enforcing unit fines for 17 types of offenses; information was recorded on fines imposed six months prior to and six months following the introduction of unit fines. Because of doubts over imposing larger fines on rich offenders, the courts set local norms for the average disposable income in their area and reduced the fines for anyone assessed at having less than the norm. The experiment examined the sums imposed and terms of payment, and the enforcement of payment. Conclusions focused on implications for the courts, fines revenue, changes in patterns of sentencing, relationship between units and installments, and calculations of disposable income. The key findings indicated that courts were able to implement the system without increasing the time needed to process cases. There was no significant change in the use of fines compared to other sentences and poorer offenders were fined less. Disparities between courts in fines imposed on poorer violators were reduced, and fines were paid more quickly. There was also a reduction in the proportion of those fined who were imprisoned for default. The four courts involved continued to use the unit fine system after the experiment ended. 3 appendixes and 18 references