Risk Matrix 2000 is a statistically derived risk-assessment instrument for use with convicted male sex offenders. It is a core element of the sex offender risk assessments carried out in England, Wales, and Scotland. This study examines its validity in a large cohort of sex offenders released from Scottish prisons. It compares 5-year outcomes with findings from the original Risk Matrix validity sample (a 1979 cohort of sex offenders in England and Wales). The instrument had moderate predictive validity and performed in a similar manner in the two studies in spite of different underlying base rates of reconviction.