© 2020, Emerald Publishing Limited. Purpose: This paper reviews the field of internal auditing (IA) post-Enron to develop insights into how IA research has developed, offer a critique of the research to date and identify ways that future research can help to advance IA. Design/methodology/approach: A structured literature review (SLR) was used to analyse 471 papers from 64 journals published between 2005 and 2018 based on a number of criteria, namely author, journal type, journal location, year, theme, theory, nature of research, research setting, regional focus, method and citations. Findings: The IA literature has not significantly contributed to knowledge of the internal audit function (IAF), and one still knows relatively little about the factors that contribute to making the impact of IA practice effective and measurable. The IA literature is US-dominated (authors and journals), focussed on the American context (publicly listed companies), reliant on positivist analyses and largely makes no explicit reference to theory. Central regions (emerging economies) and key organisational settings (private SMEs and not-for-profit organisations) are largely absent in prior IA research. This paper evaluates and identifies avenues through which future research can help to advance IA in order to address emerging challenges in the field. Originality/value: This is the first comprehensive review to analyse IA research in the post-Enron period (2005–2018). The findings are relevant to researchers who are looking for appropriate research outlets and emerging scholars who wish to identify their own research directions.