Psychosis in children and adolescents has been studied on a spectrum from (common) psychotic experiences to (rare) early-onset schizophrenia spectrum disorders. This research review looks at the state-of-the-art for research across the psychosis spectrum, from evidence on psychotic experiences in community and clinical samples of children and adolescents to findings from psychosis risk syndrome research, to evidence on early-onset psychotic disorders. The review also looks at new opportunities to capture psychosis risk in childhood and adolescence, including opportunities for early intervention, identifies important unanswered questions, and points to future directions for prevention research.