On October 1, 2015, a new standardized system of classifying disease, the ICD-10, will be imposed on practicing physicians and others in the health care sector. Since the 1980s, the U.S. has conflated the disparate goals of research and reimbursement by linking the ICD codes to payments for health care. This unwise policy will be compounded by replacing the current ICD-9 with the newer and vastly more complex ICD-10. Adoption of the ICD-10 comes with significant costs and trade-offs. This unfunded mandate not only perpetuates a misguided policy decision that confuses the disparate goals of research and reimbursement, but also adds significant financial and administrative burdens on physicians and other health care providers.