- OBJECTIVES: We used a qualitative empirical study of Canadians' values toward their health system to develop more meaningful conceptualizations of trust and health systems that can inform the pursuit of more trustworthy health systems. METHODS: We convened nine focus groups in three Canadian cities in 2002 and 2004 in conjunction with a national public opinion telephone survey of Canadians' attitudes and values toward their health system. Health system trust emerged as a significant theme in focus group discussions and was investigated using a modified grounded theory approach. FINDINGS: Respondents construct cleavages and alliances to position themselves in relation to different features of the trusted health system. The health system and Canadian Medicare are identified sources of trust just as are individual health care providers. Core to the trust relationship is the experience of vulnerability which provides the impetus for placing trust (in providers, governments and health systems) or seeds distrust, mistrust and resilience in the same. CONCLUSIONS: We offer a more robust conceptualization of what it means to trust a health system. Policy maker efforts to intervene to restore lost trust could usefully be informed by these findings.