Summary: Pursuant to an Air Force request, GAO reviewed the operation of the automated travel system (FASTravel) at Langley Air Force Base and the Pentagon, focusing on: (1) the acceptability of electronic travel records in lieu of paper travel records; (2) whether the Defense Finance and Accounting Service (DFAS) could rely on externally-generated electronic records to record obligations and generate disbursements; and (3) how the system would affect GAO travel record retention requirements. GAO noted that: (1) the Air Force could conduct a limited test of its FASTravel system; (2) although electronic records and signatures can replace paper documents, the system contains several internal control weaknesses in its electronic signature techniques; (3) the system's electronic signature validation processes are inadequate; (4) DFAS could rely on electronic travel records if adequate internal controls are implemented; (5) the FASTravel system would require individual travelers to retain travel receipts at their place of employment for a specific period of time; and (6) Air Force travelers will need detailed guidance on the new record retention policies and training on their record retention responsibilities.