Prostate cancer patients and their caregivers can face physical and psychological challenges navigating the diagnosis, treatment, and survivorship stages. To address the needs of the patient-caregiver dyad, TEMPO, a web-based, dyadic, physical activity and psychosocial self-management program was created, with a primary focus on improving quality of life. Behaviour change techniques (BCTs) were implemented as a main strategy to facilitate behaviour changes. Identifying the BCTs that successfully modify behaviour and understanding how BCTs are used may be beneficial for assessing the feasibility of TEMPO and future interventions. The goal of this study was to explore which BCTs were used and the dyads' experiences using BCTs in TEMPO. Seventeen dyads enrolled in TEMPO completed three interviews throughout the program. Interviews were transcribed verbatim and analyzed using deductive and inductive thematic analyses. The deductive analysis was guided by Michie's BCT Taxonomy to identify the BCTs discussed and the inductive analysis identified common experiences using the BCTs. The dyads described learning how to use BCTs from the step-by-step descriptions and examples provided in TEMPO. The dyads commonly referred to BCTs like goal setting, self-monitoring, and reviewing goals to enhance their behaviour changes. The dyads also described the positive outcomes as a result of using BCTs to change behaviour, like increased physical activity and improved communication. The results highlight how the dyads engage with BCTs in a behaviour change intervention. These findings can help enhance the development, design, and delivery of programs by gaining a deeper understanding of how BCTs are used by participants.