From 1996 until about 2000 the Canadian Level of Service Inventory Á Revised (LSI-R) was in use in a number of probation services in England and Wales, and it is still in use in the Jersey Probation and After-Care Service. This article reviews what has been learned about risk and need assessment in British probation through the use of LSI-R, drawing on data collected for a Home Office study and for evaluative research in Jersey. Particular areas of interest are accuracy, differences between male and female offenders, the comparative effectiveness of probation and community service, the apparent counterproductive impact of probation on low-risk offenders, and the efficacy of risk-related change measurement. The conclusion points out the wide-ranging advantages of risk/need assessment for probation services, and discusses why services in England and Wales have been slow to benefit from this.