This paper draws on findings from research in progress to discuss the ways in which EPRs are implicated in changing work practices for clinicians within the NHS in England. The study set out to question the apparent inevitability of this technology by investigating whether EPRs benefit their users. Recognising that they have been explicitly conceived to serve multiple purposes, the benefits to front line clinical users are dependent on the purposes for which EPRs are being used and the additional responsibilities and risks implied by the non-clinical interests inscribed.The study uses Actor-Network Theory as a means to investigate the relationships that constitute the EPR, and in doing so to identify the entangled sets of interests brought to bear on the realisation of this technology. The findings suggest that sharing of patient data beyond the local largely privileges secondary uses while benefits to clinicians are concentrated on locally shared EPRs.