The programme is structured around a sleep test, weekly interactive CBT‑I sessions and regular sleep diary entries. The sessions focus on identifying thoughts, feelings and behaviours that contribute to the symptoms of insomnia. Cognitive interventions aim to improve the way a person thinks about sleep and the behavioural interventions aim to promote a healthy sleep routine. The programme is designed to be completed in 6 weeks, but people have full access to the programme for 12 months from registration, including redoing sessions. They can also access electronic library articles, online tools and the online Sleepio user community. A daily sleep diary helps users track their progress and the programme tailors advice to individuals. Users can fill in the diary manually or the data can be automatically uploaded from a compatible wearable tracking device.