The AACAP Work Group on Community-Based Systems of Care, in collaboration with the American Association of Community Psychiatrists, developed the Child and Adolescent Service Intensity Instrument (CASII) as an objective, valid, and reliable decision support for level of care determination. The CASII is an evidence-based tool that has both individual patient and systems utility that is being used in many settings worldwide. As health care reform moves systems of care to greater accountability, it is essential for child and adolescent psychiatrists to learn to use tools such as the CASII. Participants learn the principles and concepts behind the construction of the CASII; understand the interpretation of dimensional criteria and the scoring of the instrument; acquire hands-on experience to rate the CASII reliably using vignettes and case studies; and understand the applicability of the CASII clinically, for quality assurance, and for outcome evaluation and research.