OBJECTIVES: Describe the development and delivery of the interventions in the Ankle Fracture Treatment Enhancing Rehabilitation (AFTER) trial, a randomised controlled trial comparing the effectiveness of supervised versus self-directed rehabilitation for adults aged ≥50 years with an ankle fracture. DESIGN: Intervention development. SETTING: UK National Health Service (NHS) hospitals. METHOD: We developed the interventions in stages. First, we reviewed two UK clinical guidelines and the existing research evidence. We then conducted a clinical practice survey (n = 59 physiotherapists) to inform a stakeholder meeting which identified key intervention components. Subsequently, we designed the interventions, tested them in a pilot trial (n = 61 participants), then refined them for the definitive AFTER trial. RESULTS/FINDINGS: The definitive AFTER trial interventions start after randomisation, which occurs when the participant's cast/boot is removed and weightbearing and ankle movement restrictions are lifted. Participants allocated to self-directed rehabilitation receive a high-quality advice workbook, a progressively challenging self-directed exercise programme that they follow to self-manage their recovery, and strategies to encourage exercise adherence. Supervised rehabilitation participants receive a high-quality workbook, then 4 to 6 one-to-one face-to-face/remote sessions with a physiotherapist. The physiotherapist provides specific advice, home exercises, and uses strategies to facilitate adherence to prescribed exercises. The supervised rehabilitation intervention is tailored to individual participants during review sessions. CONCLUSIONS: The definitive AFTER trial will provide high-quality evidence to guide rehabilitation provision for older adults with an ankle fracture. Results are anticipated in 2025. TRIAL REGISTRATION NUMBER: ISRCTN registry (identifier: ISRCTN11830323). CONTRIBUTION OF THE PAPER.