Juvenile probation officers (JPOs) are required to make numerous decisions about the case management of young offenders on a daily basis. This multi-site study examined JPOs' (N = 64) perceptions of the typical youth's risk of reoffending before implementation of a risk/needs assessment (RNA) tool, and their self-reported, case management decision-making after implementation of an RNA tool. Results indicated that JPOs tended to overestimate the likely base rates of reoffending while RNA tool estimates were more accurate. Further, most JPOs appeared to be making service referral and placement decisions commensurate with youths' risk levels, regardless of whether they claimed to use the RNA tool in their decisions. Variability in application of risk to case management practices was more a function of the probation office than of the specific JPO. Implications for use of risk assessment in juvenile probation are discussed. Copyright © 2012 John Wiley & Sons, Ltd.