This article considers the operation of peer review in the anti-corruption context. Peer review is the systematic examination and assessment of the performance of a State by other States, with the ultimate goal of helping the reviewed State comply with established standards. It is a favoured regulatory mechanism by non-governmental organisations (WTO), supranational bodies (African Union) and under multilateral conventions (OECD). Notwithstanding this, peer review is an unconventional regulatory process that is under-explored in the academic literature. To assist in addressing this issue, we begin by discussing the nature of the peer review process, its authority in international law and common procedural elements. We proceed to identify peer review as a meta-regulatory process due to its flexible and discretionary characteristics. We then consider the practical effects of peer review through a study of Australia’s implementation of the OECD Anti-Bribery Convention. We conclude that the strength of peer review lies in its function as a consensual and voluntary process operating under international law. It is a process that respects state sovereignty and influences state activities through a combination of peer pressure and reputational sanctions.