Objective: The objective of the current study was to identify challenges of making and sustaining healthy lifestyle changes for families with children/adolescents affected by obesity, who were referred to a multicomponent healthy lifestyle assessment and intervention programme in Aotearoa/New Zealand (NZ).Design: Secondary qualitative analysis of semi-structured interviews.Setting: Taranaki region of Aotearoa/NZ. Participants: Thirty-eight interviews with parents/caregivers (n 42) of children/adolescents who had previously been referred to a family-focused multidisciplinary programme for childhood obesity intervention, who identified challenges of making healthy lifestyle changes. Participants had varying levels of engagement, including those who declined contact after their referral.Results: Participant-identified challenges included financial cost, impact of the food environment, time pressures, stress, maintaining consistency across households, independence in adolescence, concern for mental health and frustration when not seeing changes in weight status.Conclusions: Participants recognised a range of factors that contributed towards their ability to make and sustain change, including factors at the wider socio-environmental level beyond their immediate control. Even with the support of a multidisciplinary healthy lifestyle programme, participants found it difficult to make sustained changes within an obesogenic environment. Healthy lifestyle intervention programmes and families' abilities to make and sustain changes require alignment of prevention efforts, focusing on policy changes to improve the food environment and eliminate structural inequities.