This chapter sets out a structured approach to treating depression in people with psychosis, with the dual aim of reducing triggers of psychotic episodes and improving quality of life and treatment motivation. It begins by clarifying why depression is often prioritized in schizophrenia treatment and reviews core assessment tools, including the Calgary Depression Scale for Schizophrenia, PHQ-9, IDS, and DASS. The chapter then presents two main intervention components: behavioral activation tailored to psychotic presentations and cognitive therapy for depression in psychosis. A detailed case vignette illustrates how these methods are applied in a patient with schizophrenia and how improvements in mood can create a foundation for further psychotherapeutic work.