Given the absence of a civil damages action for personal injury, the Health and Disability Commissioner's (HDC) complaints process occupies a pivotal role in New Zealand's medico-legal regulatory arrangements. It is designed to address complainants' non-financial motivations in making a complaint after an adverse event in their health care. This article asks whether the HDC complaints process accords its users, particularly complainants and consumers, acceptable and effective legal mechanisms for asserting their legal rights and securing just outcomes. The process is assessed against the original statutory aims of the complaints process ("fair, simple, speedy, and efficient resolution of complaints").1 Quantitative and qualitative evidence is marshalled in support of the conclusion that unacceptable barriers to accessing justice are embedded in the complaints process, as currently designed and operationalised. Of particular note are the lack of any means for a complainant to seek review of the merits of a Commissioner's decision to take no further action on a complaint, and for either party to challenge the outcome of an HDC investigation. Four reform options are considered. The author's preference is the inclusion of a mechanism for external review or appeal of adverse HDC decisions.