Data since 1980 demonstrate that the DSM-III model requires revisions in its assumptions and format. Problems inherent in the DSM-III model are considered and a paradigm shift toward a mixed categorical–dimensional classification system for DSM-V is recommended. This will reduce comorbidity, allow symptom weighting, introduce noncriterion symptoms, eliminate NOS categories, and provide new directions to biological researchers. We suggest reevaluating the threshold concept and use of quality-of-life assessment. A framework for such a revision is presented. Drawbacks to change include retraining of clinicians, administrative and policy changes, and possible reinterpretation of data collected under the DSM-III model. Nevertheless, clinicians and clinical researchers are ready for a diagnostic system that more accurately reflects the patients that they treat and study.