Adolescents living with type 1 diabetes (T1D) begin to adopt a more collaborative approach to managing T1D with their parents before becoming independent in self-management. However, adolescents can encounter difficulties with T1D management and ambiguity in relation to the division of responsibilities for T1D management with their parents. This study aimed to explore: (1) how adolescents living with T1D experience self-management of T1D and share self-management responsibilities with parents and (2) the relationship between adolescent communication with parents about T1D self-management and demographic, clinical and psychosocial variables. A meta-synthesis of qualitative literature on child and adolescent experiences of self-management of T1D was conducted. The findings of the meta-synthesis indicated that balancing the demands of self-management with other aspects of life and sense of control over T1D are important for self-management of T1D. Following this a mixed methods study involving two phases was conducted; semi-structured interviews with adolescents aged 11 to 17 years (n = 28) and a cross-sectional survey with adolescents aged 11 to 17 years (n = 113). In interviews, adolescents highlighted their experiences of gaining independence in self-management in the overarching theme ‘Navigating increasing responsibility for self-management during adolescence: “it changed gradually… and I am almost fully doing it [self-managing] now”. The following themes contributed to the overarching theme: (1) Changing levels of involvement in self-management, (2) Talking about self-management with parents, (3) Taking ownership of self-management and (4) Environmental and contextual influences affecting self-management. The findings from the quantitative phase of this study indicated that parent-adolescent communication and T1D-specific family conflict are associated with T1D self-efficacy, division of family responsibility for T1D management, activation and self-management of T1D. However, the findings also indicated that T1D-specific family conflict and parent-adolescent communication are differentially related to distinct aspects of self-management and QOL. Overall, this study identified that parent-adolescent communication and family context characteristics relate to and contribute to self-management and T1D-specific QOL in adolescents living with T1D. This research identified what factors contribute to helping or hindering adolescent engagement with self-management of T1D and specifically that adolescents’ perceptions of their communication with their parents about T1D management are important. For the first time, the findings provide a nuanced understanding of adolescent perspectives on self-management of T1D and communication with parents about T1D self-management. Promoting self-efficacy through targeting communication strategies employed by adolescents and their parents may result in more optimal sharing of responsibilities, improved self-management and better QOL for adolescents living with T1D.