Volume 3 of the International Classification of Diseases 9th Revision Clinical Modification (ICD-9-CM) has been used in the U.S. for the reporting of inpatient pro- cedures since 1979. The structure of Volume 3 of ICD-9-CM has not allowed new procedures associated with rapidly changing technology to be effectively incorporated as new codes. As a result, in 1992 the U.S. Centers for Medicare and Medicaid Services (CMS) funded a project to design a replacement for Volume 3 of ICD-9-CM. After a review of the preliminary design, CMS in 1995 awarded 3M Health Information Systems a three-year contract to complete development of the replacement system. The new system is the ICD-10 Procedure Coding System (ICD-10-PCS).