[영문]Federal HIPAA legislation mandates that the National Provider Identifier be fully implemented across all healthcare entities between May 2005 and May 2007 or 2008 for small payers. Starting May 2005, healthcare providers will be eligible to obtain an NPI and use these numbers to submit claims or conduct other transactions specified by HIPAA. By 2007, the NPI must be used in connection with the electronic transactions identified in HIPAA. This article will use software and data experts?knowledge as well as the authors' NPI implementation readiness assessment work to review the impact to both payers and providers, including hospitals, clinics, and other service entities. The authors will suggest planning, budgeting, architecting, and data management solutions for payers and providers to achieve the optimal administrative simplification goals intended by the NPI, without compromising data integrity and interoperability objectives across the service spectrum of the healthcare enterprise.