Singapore’s Agency for Care Effectiveness (ACE) was established in 2015 to conduct health technology assessments (HTAs) to inform national funding recommendations for cost-effective treatments. Initially, only clinicians were consulted to ensure the HTAs were relevant to local clinical practice and patients’ needs. In 2021, a workstream to support patient participation in ACE’s work was established. Stakeholder mapping was conducted to identify all local patient groups and determine their capacity to meaningfully participate. A Consumer Panel was appointed as the collective voice of patients and carers to provide strategic advice on priority setting, and propose opportunities to foster collaborative working relationships and overcome local barriers to patient participation. Training resources to encourage patient participation in topic selection, HTAs, and the development of educational tools were co-developed with local patient organisations, drawing upon international best practices and contextualised to meet local patients’ preferences. Continuous process improvement in response to feedback from patients, and providing regular advice to patient organisations on how their inputs have been used, have increased patient participation in ACE’s work and improved the quality of inputs received. Future efforts will focus on implementing more patient participation opportunities, and measuring the impact patients’ inputs have on healthcare decision making.