This 2012 edition was designed to be used as a tool by state DOT auditors, Architectural/Engineering (A/E) firms, and public accounting firms that perform audits and attestations of A/E firms. The techniques presented herein focus primarily on examination, auditing, and reporting procedures to be applied to costs that are incurred by A/E firms for engineering and design related services performed on various federal, state, and local transportation projects. This guide provides general guidance only and is not meant to supersede the Federal Acquisition Regulation (FAR) or any related laws or regulations. Users should be aware that the FAR Cost Principles change frequently; accordingly, the applicable FAR version should be referenced in conjunction with the use of this guide.