The first step in effective management of schizophrenia is an accurate diagnosis. The Canadian Guidelines for the Assessment and Diagnosis of Patients with Schizophrenia Spectrum and Other Psychotic Disorders is a recent guideline on assessment and diagnosis. Keys to accurate diagnosis include a structured assessment that includes using the Structured Clinical Interview for DSM-5 (SCID-5). Assessment should be based on all sources of information, which can include family, other contacts, other clinicians, and history. If uncertainty remains about the diagnosis of a patient, a second opinion or consultation can be valuable.