This article describes the rationale underlying the development of an evidence-based kaupapa Māori programme for diabetes in primary care – Mana Tū: a whānau ora approach to type 2 diabetes. Mana Tū was designed by the National Hauora Coalition, a Māori-led Primary Health Organisation (PHO) based in Auckland, in response to current ethnic and social inequities in type 2 diabetes rates, outcomes and wider determinants. This unique model of care supports people with poorly-controlled type 2 diabetes to successfully self-manage their condition. In 2017, the National Hauora Coalition was awarded a Long-Term Conditions Partnership Research grant to test the effectiveness of Mana Tū. The programme incorporates input from patients with type 2 diabetes and primary care doctors, and aims to address system, service and patient factors that prevent whānau to ‘stand with authority’, or ‘mana tū’, when living with a long-term condition. Mana Tū focuses on the wider determinants for health by identifying both health barriers (including lack of knowledge around healthy eating, what medications do and physical activity) and social barriers (including financial, housing and transport issues). Over the next 2 years, clinical, implementation and cost-effectiveness data will be collected and analysed.