Preprint of article published in: Auditing: A Journal of Practice & Theory, 32(1), February 2013 This study presents a review of academic research on audit quality. We begin with a review of existing definitions of audit quality and describe general frameworks for establishing audit quality. Next, we summarize research on indicators of audit quality, such as inputs, process, and outcomes. Finally, we offer some suggestions for future research. The study should be useful to academics interested in audit quality as well as to the Public Company Accounting Oversight Board (PCAOB) and other regulators.