Over the years, GAO has developed a substantial body of law and standard procedures for considering bid protests. This is the tenth edition of Bid Protests at GAO: A Descriptive Guide, prepared by the Office of the General Counsel, to aid those interested in GAO's bid protest process. We issued the first edition of this booklet in 1975 to facilitate greater public familiarity with the bid protest process at GAO and we have revised it over the years to reflect changes in our bid protest procedures. This edition incorporates changes made to our Bid Protest Regulations, effective May 1, 2018, to conform the regulations to reflect administrative changes in our procedures enacted by section 1501 of the Consolidated Appropriations Act, 2014, Pub. L. No. 113-76, 128 Stat. 433. Section 1501 required GAO to establish an electronic filing and document dissemination system for the filing of bid protests at GAO. The statute also provided for GAO to receive a fee from filers to support the establishment and operation of the electronic system. This edition also incorporates changes to our protective order process.