Publisher Summary This chapter discusses a second strategy of identifying important differences among offenders. It also discusses classification strategies that are administered to all members of a correctional setting, usually upon admission. Risk assessment instruments, for example, are administered shortly after conviction and classify offenders according to high, medium, and low potential for absconding, violating conditions, and committing new offenses. The chapter also devotes considerable attention to screening offenders for needs that should be addressed in correctional treatment programs. Correctional practitioners are advised to give priority to those needs that are related to future offending. The chapter also discusses new developments in correctional assessments—gender-responsive risk assessments and assessments specific to special populations such as sex offenders.