The developmental phase and preliminary psychometric data are reported for an Australian adaptation of an assessment inventory for juvenile offenders. Specifically, the Australian Adaptation of the Youth Level of Service/Case Management Inventory (YLS/CMI-AA, Hoge, & Andrews, 1995) is used to assess risks, needs and strengths to inform decision making with juvenile offenders. Data from a sample of 290 juvenile offenders were used to analyse item and score characteristics which, with few exceptions, performed in keeping with traditional psychometric standards. Predictive validity in a subsample of 174 males followed for recidivism between 6 and 32 months resulted in a correlation of 0.28 and area under the receiver operating characteristic (ROC) curve of 0.67 for the total score on the inventory. The results and use of the inventory are placed in the context of related developments in other jurisdictions.