The IIA's 2026 Three Lines Model Update: A Critical Review of Its Strengths and Blind Spots

The IIA's 2026 update to the Three Lines Model aims to align with new Global Internal Audit Standards and reorient towards board-level concerns regarding assurance and advice. While the update commendably acknowledges the practical overlaps and resource constraints faced by organizations, it introduces a significant blind spot: the financial burden of maintaining independence in smaller structures. The article critically examines how the model's safeguards, though theoretically sound, become unworkable for entities with limited budgets, highlighting a paradox where the solution assumes away the very problem it seeks to address.