Sleep Ninja® is a free, evidence based smartphone app shown to be effective in helping young people with sleep problems. By addressing good quality sleep, we are setting up the foundations to promote emotional, social and physical wellbeing and academic performance, now and in the future. Sleep Ninja® was designed and developed at the Black Dog Institute in consultation with young people, their parents/carers, psychologists, counsellors, and sleep experts. It is the first adolescent-focused app which helps young people improve their sleep. It's free to use and backed by research.