Precision Medicine in Child and Adolescent Psychiatry: The Potential, Limitations, and Prospects for Diagnosis and TreatmentAbstract: Precision medicine has transformed several areas of pediatrics, whereas diagnostic assessment and treatment in child and adolescent psychiatry continue to rely predominantly on syndrome-based classification systems. This narrative review examines the opportunities and limitations of applying precision psychiatry in children and adolescents. We summarize key conceptual frameworks, including the Research Domain Criteria (RDoC), the Hierarchical Taxonomy of Psychopathology (HiTOP), and developmental psychopathology as well as methodological approaches such as genetics, neurophysiology, digital phenotyping, and machine learning. We further discuss potential clinical applications in attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, depressive disorders, and the early detection of psychosis. In addition, this article critically reviews the methodological, developmental, ethical, and practical challenges associated with implementing precision psychiatry in routine clinical care. Although precision psychiatry holds considerable promise for improving early detection, prognostic assessment, and individualized treatment selection, most approaches remain at the research stage. The integration of biological markers with developmental psychopathology and comprehensive clinical assessment appears particularly promising for advancing personalized diagnosis and treatment in child and adolescent psychiatry.