Purpose: In 2016, the National Standards for School-based Initial Teacher Training (ITT) Mentors were published in England. The purpose of this paper is to critique these standards through a comparison of how others have framed and defined the role of the mentor, drawing on equivalent standards already published in nursing (2008) and social work (2012). Design/methodology/approach: An analysis of three sets of professional standards was conducted by adapting the "constant comparison" approach in which the researchers sought to combine a form of inductive coding with comparison across the texts. This enabled the identification of a number of common themes and omissions across the three sets of standards. Findings: The analysis revealed the ITT mentor standards provide a comparatively limited account of the role of the mentor, particularly in relation to the process of assessment, the power dynamics between mentors and student teachers, and the school as an institutional site for professional learning. Originality/value: The study's originality lies in the inter-professional comparative analysis, which revealed a number of potentially contentious issues not immediately apparent from a close textual analysis of the ITT mentor standards.