BACKGROUND: Understanding quality improvement from a patient perspective is important for delivering patient-centred care. Yet the ways patients define quality improvement remains unexplored with patients often excluded from improvement work. We examine how patients construct ideas of 'quality improvement' when collaborating with healthcare professionals in improvement work, and how they use these understandings when attempting to improve the quality of their local services. METHODS: We used in-depth interviews with 23 'patient participants' (patients involved in quality improvement work) and observations in several sites in London as part of a four-year ethnographic study of patient and public involvement (PPI) activities run by Collaborations for Leadership in Applied Health Research and Care for Northwest London. We took an iterative, thematic and discursive analytical approach. RESULTS: When patient participants tried to influence quality improvement or discussed different dimensions of quality improvement their accounts and actions frequently started with talk about improvement as dependent on collective action (e.g. multidisciplinary healthcare professionals and the public), but usually quickly shifted away from that towards a neoliberal discourse emphasising the role of individual patients. Neoliberal ideals about individual responsibility were taken up in their accounts moving them away from the idea of state and healthcare providers being held accountable for upholding patients' rights to quality care, and towards the idea of citizens needing to work on self-improvement. Participants portrayed themselves as governed by self-discipline and personal effort in their PPI work, and in doing so provided examples of how neoliberal appeals for self-regulation and self-determination also permeated their own identity positions. CONCLUSIONS: When including patient voices in measuring and defining 'quality', governments and public health practitioners should be aware of how neoliberal rationalities at the heart of policy and services may discourage consumers from claiming rights to quality care by contributing to public unwillingness to challenge the status quo in service provision. If the democratic potential of patient and public involvement initiatives is to be realised, it will be crucial to help citizens to engage critically with how neoliberal rationalities can undermine their abilities to demand quality care.