For those who have to deal with offenders, either directernat indirectly, conducting assessments is simply part of their regular work routine. Any intervention with an offender requires an assessment of how the characteristics of the offender and the situation are related to a relevant outcome. Within a correctional context, there are many outcomes of interest. A correctional officer, for example, may need to judge whether a depressed inmate is suicidal. Parole board members consider the likelihood of an inmate adjusting to life in the community. A therapist must assess an offender’s progress in treatment. The list can go on, but these examples are sufficient to demonstrate that offender assessments are not only common activities but also that the results from these evaluations are important to correctional staff, offenders, and the community. In this article, I summarize what we know about offender risk assessment and suggest to practitioners some guidelines for the selection and use of risk instruments. Given that the reduction of criminal behavior is one of the major goals of most correctional systems, my focus is on the assessment of risk for recidivism. The article is not intended to provide a critical review of the many psychological tests and offender classification instruments used in the field. Granted, we can use such a review, and many of the articles in this issue provide evaluations of some offender assessment instruments. The research literature is sufficiently robust to offer general suggestions about what should constitute good correctional assessment. Thus, this article is outlined as a set of guidelines along with a supporting rationale.