The study and treatment of juvenile victimization would greatly benefit from instruments that are comprehensive, methodologically sound, and relevant to settings such as health and mental health clinics, criminal justice institutions, and child protection agencies. Toward these ends, this article makes 20 recommendations. Among other things, instruments should (1) allow victimization to be mapped onto conventional crime and child protection system categories; (2) adequately assess victimization by family and other nonstranger perpetrators; (3) ask about crimes specific to childhood, such as nonviolent sexual offenses and neglect; (4) allow for comparisons between juvenile and adult victimizations; (5) collect self-report data with children as young as age 7 years; (6) use simple, behaviorally specific language; (7) protect privacy during data collection; (8) attend to potential ethnic, class, and gender differences; and (9) prepare procedures to assist children in danger. Comprehensive and well-researched instrumentation could greatly advance the study and treatment of juvenile victimization.