Researchers who study injury morbidity frequently use hospital discharge, emergency department, trauma registry or other morbidity data that have been coded using the clinical modification of the International Classification of Diseases, 9th Revision (ICD-9-CM). The US Department of Health and Human Services has ruled that the clinical modification of the 10th Revision of ICD (ICD-10-CM) will replace ICD-9-CM in the United States for coding of morbidity data beginning October 1, 2015. On that date, all hospitals and health care providers covered by the Health Insurance Portability and Accountability Act (HIPAA) must use ICD-10-CM when reporting medical diagnosis information. This topic symposium will provide an overview of the ICD-10-CM injury diagnosis and external cause codes as well as the proposed ICD-10-CM matrices for standardised reporting and classification of injuries by (1) mechanism and intent of injury and (2) nature of injury and body region. A proposed ICD-10-CM surveillance definition for traumatic brain injury (TBI) will also be presented. Symposium participants will be encouraged to provide feedback on the proposed matrices and definitions. In an interactive exercise, participants will learn how to use General Equivalence Mappings (GEMs) to develop crosswalks to translate between ICD-9-CM and ICD-10-CM.