Despite evidence of positive impact, telemonitoring (TM) interventions for the management of heart failure (HF) have seen limited adoption in Canada. Following a literature review that explains evidence inconsistencies on contextual differences between trials, a single case study of the Medly TM program sought to understand the factors that influence the successful implementation, scale, and spread of HF TM. First, an implementation evaluation found that the Medly program was successfully implemented due to facilitators related to characteristics of the clinic and of the adopting clinicians. Barriers that could limit the program’s sustainability, scale, and spread included complexity of the intervention, costs, and the lack of implementation plan. Because successful spread is only possible if interventions are used as intended, the second study explored patient adherence to taking daily TM readings. Results showed an overall average adherence rate of 73.6% (SD 25.0) with a significant decline over time; the decline was significantly steeper in patients of younger compared to older age groups (P=0.04). Adherence rates were further explained by patients’ perceptions of the program’s benefits, ease of use, presence of supporting services, and patients’ ability to form a habit around taking daily TM readings. Finally, because successful implementations generally require the adaptation of interventions to local contexts, a qualitative study identified components of the TM program that could be safely adapted without negatively influencing the program’s ability to yield desired outcomes. The spread of HF TM has been slowed by intervention and contextual complexities. This thesis describes key insights that have led to the development of an implementation strategy for TM programs to mitigate these barriers in the future. As such, this research has contributed to clarifying a path toward the wider adoption of HF TM such that it is available across Canada for HF management.