Accounting research has increasingly been concerned to investigate professional expertise. This paper contributes to this interest by examining the process by which state (or government) auditors may become recognized as possessing expertise relevant to guiding and implementing new public management reforms. We analyze this process in the Canadian province of Alberta to understand the construction of a claim to expertise, drawing on theories in the social study of science and technology. Specifically, through our study of the development and consolidation of a network of support, we examine how the Office of the Auditor General of Alberta anchored its claims to expertise in the corpus of knowledge on measurement of government performance; the various devices that the Office used to sustain these claims; and the ways in which government and public servants reacted to them. In particular, our paper provides insights into how standards of "good practices" develop through a process of "fact" building, which involves the undertaking of local experiments by practitioners, the, production of inscriptions in reports, and their subsequent validation by other practitioners. The production of inscriptions in sites of occupational practice such as those operated by government audit offices, and the collective process of validation that subsequently takes place in the practitioner community, are significant aspects in the construction of networks of support around claims to expertise. (c) 2006 Elsevier Ltd. All rights reserved.