Psychometric assessment adds a norm-based reference to the clinical interviews and historical information that provide a foundation from which an adolescent's offense behavior can be interpreted. The psychometric assessment can assist in determining placement in an appropriate treatment program, developing a viable treatment plan, and assessing treatment progress. A comprehensive test battery needs to be cost-efficient and time-efficient; to demonstrate reliability, validity, and utility; and to be age-appropriate. A basic test battery should assess all clients and can be supplemented with more specialized testing when additional information is needed. The sample test battery presented here is currently being used at Mille Lacs Academy, a Nexus treatment program located in Minnesota. This private, nonprofit inpatient facility treats juvenile male sex offenders ages 11-18 who are referred by courts, social services, mental health agencies, other treatment programs, and private individuals. Most have histories of prior treatment failures. The average length of treatment is 12-18 months. The test battery focuses on intellectual and neurological functioning, personality functioning and psychopathology, behavioral assessment, and sexual deviance. Clinicians use the battery to plan intensive treatment to remediate deficits that suggest that a client is unmotivated for treatment. 31 references