AASHTO UAAG-4, Uniform Audit and Accounting Guide, 2016 Edition, provides guidance for audits of architectural and engineering consulting firms. Chapter 1 sets out the organization of the guide and defined terms, and Chapter 2 addresses the adequacy of accounting records, including indirect cost rate schedules, unallowable costs, financial statements, management representations, and the roles of management and the CPA. Chapter 3 covers standards for attestations and audits, including engagement types, auditing standards, and opinions on internal control. Chapter 4 treats cost principles drawn from Federal Acquisition Regulation Part 31 and from state and local cost principles, covering allowability, allocability, direct and indirect costs, cost accounting standards, and allocation bases for indirect costs. Chapter 5 addresses cost accounting and Chapter 6 covers labor-charging systems. The guide is intended for state DOT auditors, A/E firms, and public accounting firms performing these audits.