This chapter begins with an explanation of what psychosis and bipolar disorder are and how common psychosis and psychotic experiences are in young people. The importance of non-stigmatising and normalising approaches to engage young people is highlighted, and the treatability of psychosis is emphasised. It moves on to explain the stress vulnerability model of psychosis and the special developmental context for children and young people that can make them more susceptible to experiencing psychotic symptoms. An understanding of signs and symptoms is provided, and a case study is used to help highlight the opportunities for early detection and help and the role that non-mental health specialists can play in this. This includes when and how to refer to specialist early intervention services. Psychological frameworks for understanding how psychotic symptoms develop and the specialist care pathways and services available to prevent progression to a psychotic illness and to help young people recover are outlined. This includes a summary of evidence-based treatments. The importance of early intervention and prevention is emphasised, including information about how best to support young people experiencing psychotic phenomenon that you may come across in your work setting, as a non-mental health professional, and their parents/carers.