(DCAI), located in Sandy Springs, Georgia. Its teaching staff maintain a library of self-study courses as well as providing seminars by live instructors to meet the training requirements of DCAA employees. On a limited basis, the institute also provides training for other government agencies and foreign military employees. Defense contract audits Defense contract audits are required to be performed in accordance with Government Auditing Standards. These standards, commonly referred to as the "Yellow Book", are published by the Comptroller General of the United States. Policies and guidelines more specific to defense contract auditing are detailed in the Defense Contract Audit Manual, a continuously updated online publication of the DCAA. The objective of a contract audit is to express an opinion, in the form of an auditor's report, on a contractor's cost estimates or cost claims, depending on the type of contract. This involves evaluation of the contractor's policies, procedures and other internal controls over contract costs, and examining samples of supporting records for individual transactions. Government Auditing Standards require the contract auditor to maintain strict independence during audits, avoiding relationships and situations that would look questionable to third parties. Contractor responsibility The Federal Acquisition Regulations (FAR) assign responsibility to the contractor for maintaining sufficient records to support claimed costs. FAR 31.201-2(d) requires the contractor to keep "records, including supporting documentation, adequate to demonstrate that costs claimed have been incurred, are allocable to the contract, and comply with applicable cost principles". The same FAR provision allows a government agency's contracting officer to "disallow all or part of a claimed cost that is inadequately supported." A major area of emphasis in a DCAA audit is determining the adequacy and reliability of the contractor's records to prove the accuracy and reasonableness of contract costs. FAR 4.703(a) requires contractors to "make available records, which includes books, documents, employee time & attendance records, accounting procedures and practices, and other data ... to satisfy contract negotiation, administration, and audit requirements". 2008 allegations of intimidation, retaliation, lax oversight, and poor performance A report released by the Government Accountability Office (GAO) on July 23, 2008, alleged that DCAA managers threatened a senior auditor with personnel action if he did not remove negative findings from a report criticizing a large federal contractor. The report found a too-cozy relationship between management at the DCAA and some of the contractors they are assigned to audit, including Boeing. GAO also said auditors