Abstract:The regulation of professional groups has often been justified as being in the public interest. In recent decades, policymakers in Anglo-American countries have questioned whether self-regulating professions have truly served the public interest, or whether they have merely acted in their own interests. This paper draws on legislative records and policy reports to explore meanings attached to professional self-regulation and the public interest in Canada by state actors over the past 150 years. The findings point to a shift in the definition of the public interest away from service quality and professional interests, towards efficiency, human rights, consumer choice, and in some contexts business interests. Changing views of the public interest contribute to regulatory change.Keywords: Professions, public interest, self-regulation, Canada, historical change, state actors.Over the last 50 years there has been considerable debate amongst Anglo-American policymakers and academics alike about whether professional self-regulation is truly in the public interest (Devlin & Chang, 2010; Rees, 2013; Paton, 2008). Selfregulating professions including medicine and law have been rocked by scandals. Formerly among the most trusted people in society, increasingly the public views lawyers, medical doctors, and other professionals more cynically, as individuals who too often put their own interests above those of their clients (Paton, 2008). The rising costs of professional services, combined with scandals surrounding professional misconduct, have provoked a complete restructuring of professional regulation in law and medicine in the UK (Flood, 2011; Paton, 2008;Dixon-Woods, Yeung, & Bosk, 2011). Here, medical doctors, lawyers, and other professionals are no longer technically self-regulating; while they have a voice in the regulatory process, the majority of people on regulatory boards are non-professionals (Dixon-Woods et al., 2011; Paton, 2008). Australia has recently implemented similar legislative change to reduce self-regulation and enhance government oversight (Rees, 2013; Paton, 2008). Threats to professional self-regulation have also been identified within the US (Paton, 2008). Regulatory change has been justified on the grounds that it is necessary to serve the public interest. Despite these challenges, professional self-regulation persists in Canada (Rees, 2013; Paton, 2008), which some law scholars have labelled "the last bastion of unfettered self-regulation" in the world (Rhode & Woolley, 2012, p. 2774. Legislation regulating professions in Canada charges professional bodies with the responsibility of upholding the public interest.In debates about professional regulation, many commentators write about the "public interest" as if it is easily and objectively defined; however, the elasticity with which the term is used suggests that it is a social construction and therefore subject to contest and change. Both defenders and challengers of professional self-regulation make their case on public interest grou...