Social workers in health and mental health and across public and private health sectors are expected to be knowledgeable of comprehensive approaches to effectively serve individuals dealing with psychotic disorders, including family members involved in their care. Effective services require expertise in assessment, diagnostics, treatment planning, and coordination of community support services. This article provides a knowledge base for social work practitioners working with clients challenged by the experience and consequences of serious mental illness, such as schizophrenia spectrum and other psychotic disorders. We begin by reviewing the public health significance of these disorders, clinical phenomenology and its historical context, and symptoms and classification. We then discuss the family and cultural context, evidence-based treatments, and several social and clinical issues that social work practitioners should be aware of when working with this client population.