Objective: To explore how technologies are used and experienced in rehabilitation. Design: A qualitative study using a grounded theory approach within a randomized controlled trial investigating the effectiveness of tailored, affordable technologies to improve mobility and physical activity. Settings: Aged care and neurological rehabilitation wards with community follow-up. Participants: Twenty patients undergoing rehabilitation and randomized to the experimental arm of a trial (mean age 64 years (SD 23)) were recruited for interviews, plus 11 physiotherapists involved in technology prescription as part of the trial. Method: Two interviews per patient (one in hospital, one post-discharge) and four focus groups with physiotherapists were conducted. Transcribed data were coded and synthesized. Memo-writing and constant comparison methods guided data analysis. Results: A process of patient engagement with technology involving two stages: (1) initial patient engagement and (2) maintaining patient engagement was identified. Therapists used a series of steps and strategies to gain and maintain patient engagement. A positive first experience and continued input into patient programmes was needed. The level of patient engagement was not consistent across the duration of the trial, increasing or decreasing due to changes in the technologies prescribed or setting of use. Two conditions were key to optimizing patient engagement: sufficient support and perceived benefit from using technology. Conclusions: Patients can engage with technology during rehabilitation when prescription is tailored by a therapist. Perceiving benefit from using technology, in addition to receiving the right support to enable use appears to influence the level of patient engagement.