Background: Obesity is higher in people with intellectual disabilities. Aims: There are two aims of this explorative paper. Firstly, using a realist lens, to go beyond 'what works' and examine the 'context, mechanisms and outcomes' (CMO) of lifestyle/obesity programmes for this population. Second, using a logic model framework to inform how these programmes could be implemented within practice. Method: We explored six-review papers and the individual lifestyle/obesity programmes that these papers reviewed using the CMO framework. Results: There were few theoretically underpinned, multi-component programmes that were effective in the short to long-term and many failed to explore the 'context and mechanisms'. We developed a logic model and engaged in two co-production workshops to refine this model. Discussion: Using a realist approach, programmes need to be underpinned by both individual and systems change theories, be multi-component, have a closer understanding of the interplay of the 'context and mechanisms', and co-designed using a logic model framework.