Health, especially the lack of it, raises questions not only about diagnosis and treatment but also about trust: in one’s body and its responses, in individual health care professionals and informal care givers, in medical knowledge and in health care systems. Digital technologies affect all of these with the growing use of self-monitoring and diagnostics as well as easier availability of professional medical journals via the internet and online fora for patients to discuss their experiences of everything from drug reactions to doctors’ skills to hospital car parking facilities. Drawing on ongoing research about online direct-to-consumer genetic testing, this paper examines the ways in which digital technologies reconfigure trust relationships between people, their bodies, codified and experiential knowledge, and the techno-bureaucratic systems which shape these relationships.