Co-design is a term commonly used to describe involving people with lived experience in program, policy and research design and its outcomes. However, the implementation of co-design is inconsistent due to a lack of an agreed-upon definition, framework, and set of principles for application. This article describes a set of guiding principles for genuine co-design with children and young people with disability in Australia. 

The article synthesises the existing Australian evidence and validates this evidence base through collaborative autoethnographic reflections of the co-authors’ collective experience in a co-design team. Drawing together themes and insights from this process, four relationally driven guiding principles for genuine co-design that can be applied in Australian as well as international settings are developed: 

• personalised: building trust and safety over time
• holistic: embedding co-design across the project lifespan
• reflexive: considering and sharing power
• inclusive: prioritising accessibility and diversity.