This research is based on an in-depth analysis of 34 interviews with partners in Big 4, medium-sized, and small audit firms that specialize in private and/or public company audits, to explore how they understand the concept of audit quality. Two contrasting conventions—i.e., shared judgment norms—of audit quality emerge from the analysis. Public company audit partners in Big 4 firms espouse what we call the “model” audit quality convention, which considers that audit quality results from a technically flawless audit, where professional judgment is highly formalized, and quality is attested by a perfectly documented audit file that passes Canadian Public Accountability Board (CPAB) and PCAOB inspections. In contrast, partners working primarily on private company audits, regardless of their firm's size, endorse what we call the “value-added” audit quality convention, which considers that audit quality results from tailoring the audit to meet the client's unique needs, where professional judgment is unconstrained, and where quality is attested by the client's perception that the audit has given a better understanding of their financial situation and the associated risks and opportunities. Our analysis also reveals significant tensions within each of these two conventions, and a fear that the current regulatory framework for quality control might end up severely hurting audit quality.