Aims:To explore participants' experiences with and perspective of a telephonebased, peer-led diabetes self-management intervention targeting adults with type 2 diabetes (T2D) from speciality care settings. We also sought to identify areas for improvement for future iterations of the intervention.Methods: This study recruited 25 adults with T2D from the intervention arm of a randomized controlled trial of a peer support intervention for diabetes. Individuals took part in semi-structured interviews that explored the following topics: perceived impact of the intervention, relationship with peer leader, desirable characteristics in a peer leader, and suggestions for improving the intervention. Focus groups were recorded, transcribed, quality checked, coded, and analysed to develop themes and subthemes.Results: Four core themes emerged: (1) importance of the 'participant-peer leader' match, (2) peer leader roles and responsibilities, (3) need for flexible support models, and (4) factors affecting intervention implementation and engagement. The quality of the participant-peer leader relationship appeared to be linked to intervention satisfaction. Beyond demographic features such as age and sex, key characteristics for forming a strong match included stage of life, lifestyle, diabetes-related factors, and communication style. Conclusions: Participants have unique ideas about what support should look like and preferences for how support is best delivered. Future models of peer support need to be customizable to individuals' needs and responsive to changes in life circumstances. If participants are the decision makers in the matching process, they may experience greater satisfaction and derive maximal benefits.