Authentication is a generic term that includes any method of establishing the authorship of a record entry, such as a handwritten or electronic signature. The Centers for Medicare & Medicaid Services (CMS), as outlined in the Medicare Program Integrity Manual, chapter 3, "require that services provided/ordered be authenticated by the author." Any practitioner providing services to patients (Medicare and non-Medicare) must be aware of the requirements for authenticating the documentation maintained in the medical record. Signatures are the culmination of the procedure and services provided and identify the billing practitioner and owner of the work provided. Failure to provide and validate appropriate signature authentication in the documentation makes it very difficult to support the fact that the service was provided. Neglecting to follow authentication requirements can result in the denial or recoupment of payments.