This practical new guide on the 2002 AAIDD Definition Manual tells clinicians, educators, policy makers, and program managers how to implement the various components of the AAIDD definition system in their specific job settings. The authors discuss the contemporary relevance of the supports-based AAIDD definition in the context of issues ranging from special education practices and IDEA mandates, to diagnosing individuals with a higher IQ and conducting retroactive diagnoses such as in the Atkins v. Virginia case. Policy makers and program managers will benefit from discussions on how the supports paradigm can improve quality outcomes of programs, and how the 2002 system incorporates the emerging consensus in the field to move towards a supports-based approach. Learn more about the 2002 definition system on p. 6.