The Department of Health and Human Services (DHHS) provided guidance regarding contingency planning for the implementation of the NPI. For some time after May 23, 2007, Medicare Fee for Service (FFS) will allow continued use of legacy numbers (Unique Physician Identification Numbers (UPINs) and Provider Identification Numbers (PINs)), as well as accepting transactions with only NPIs. The effective date for providers to use only the NPI only on claims and to cease entering UPINs and PINs will be officially announced at a later date.