Book excerpt: The globalization of psychology is already in full effect in the United States as psychologists find themselves treating clients of varying nationalities and cultural backgrounds. The World Health Organization's International Classification of Diseases (ICD) has been a major factor in the creation of international standards for diagnosis and is already used in many medical practices throughout the country, yet it has not been fully integrated into the mental healthcare system. As such, this book provides psychologists with a brief yet thorough overview of the tenth edition of the ICD with clinical modifications for the US (ICD-10-CM) and will prepare them for its increased prevalence. Readers will come away with an understanding of the history and rationale behind this system of diagnosis, and they will learn how to integrate the coding system and its nuances into their everyday practices. They will also be prepared for upcoming revisions to the ICD-10-CM and the eventual transition to the ICD-11 that will change how psychologists do business.