Although risk assessment is part of a regime leading to various efforts to reduce risk by treatment and aftercare, all instruments show good predictive validity. However, depending on the instrument, recidivism category, and subgroup, the predictive accuracy varies markedly. Furthermore, the authors fail to demonstrate predictive validity for sexual violent reoffences - for the whole sample and for all subgroups. The results, nevertheless, support the utility and predictive validity of actuarial risk assessment complementary to treatment efforts to reduce risk. On the other hand, forensic practitioners have to be aware of the limitations of actuarial risk assessment methods, in particular as regards to variable predictive accuracy for different sexual offender subgroups and reoffence categories. Tables, notes, and references (Published Abstract)