Schizophrenia and other psychotic disorders represent some of the most complex and severe mental health conditions, characterized by a profound disruption in an individual’s thoughts, perceptions, emotions, and behavior. This chapter provides a comprehensive and practical guide for psychiatric nurses on the evidence-based care of clients experiencing psychosis. It begins by defining key terms and outlining the diagnostic criteria for schizophrenia and related disorders. It explores the multifactorial etiology of psychosis, integrating the evidence on genetic, neurobiological, and environmental risk factors. A significant focus is placed on the nursing process, detailing holistic assessment strategies and tailored interventions for managing positive, negative, and cognitive symptoms. The critical role of the nurse in safely administering and monitoring antipsychotics, including the management of common side effects, is examined. Furthermore, the chapter emphasizes the importance of psychosocial interventions, patient and family education, and relapse prevention strategies to support long-term recovery and successful community reintegration. Through clinical vignettes, flowcharts, and practical tables, this chapter equips nurses with the essential knowledge and skills to deliver compassionate, competent, and effective care to this vulnerable population.