In England, the national mortality review programme for people with intellectual disabilities, the LeDeR programme, was established in 2015. The programme supports local areas to review the deaths of all people with intellectual disabilities aged 4 years and over. Each death has an initial review; if indicated, a full multi-agency review takes place. The learning from the mortality reviews contributes to service improvements locally and nationally. This paper describes the programme's introduction and processes, exploring the challenges faced, and the successes achieved. It considers the background and rationale for the programme and the steps taken during its implementation, in order that others can learn from our experiences. Now the programme is established, its focus needs to shift so that we have a better understanding about how the findings of mortality reviews are leading to local and national service improvements and their impact.