Offender risk and needs assessment, one of the pillars of the risk-need-responsivity model of offender rehabilitation, usually depends on raters assessing offender risk and needs. The few available studies of interrater reliability in offender risk assessment are, however, limited in the generalizability of their results. The present study examined interrater reliability in Dutch offender risk assessment by 38 raters who independently assessed 75 offenders. The results show substantial reliability (Tinsley and Weiss's "T" value greater than or equal to 0.61) for risk of reconviction and moderate ("T" value greater than or equal to 0.41) to substantial reliability for offender needs, such as accommodation, finances, or education. These results are discussed in light of a recent British study on the interrater reliability of a comparable risk assessment instrument. The results from the present study show similar to better reliability, leading to the conclusion that greater external validity does not negatively influence interrater reliability results. (Contains 3 tables and 2 notes.)