Over the past 15 years, the use of specialised medical equipment by patients at home has increased in most industrialised countries. Adopting a conceptual framework that brings together two research perspectives, i.e. the sociology of technology and the sociology of illness, this paper empirically examines why and how patients use health technology at home and in the broader social world. Our study compares and contrasts the use of four interventions: antibiotic intravenous therapy, parenteral nutrition, peritoneal dialysis and oxygen therapy. We conducted interviews with patients (n = 16) and caregivers (n = 6), and made direct observations of home visits by nurses (n = 16). The content and structure of patient manuals distributed by major manufacturers and hospitals were analysed (n = 26). The aim of our study was to determine how technology was supposed to be used versus how it was actually used. This study shows that patients are deeply ambivalent about the benefits and drawbacks of technology, and that these advantages and disadvantages are shaped by the various places in which the technology is used. While technology can be pivotal in making patients autonomous and able to participate in the social world, it also imposes heavy restrictions that are intimately interwoven with the nature of the particular disease and with the patient's personal life trajectory.