Delirium is a syndrome characterized by altered consciousness, attention, affect, and cognition. It is a common clinical presentation of medical and surgical conditions that manifests with heterogeneous combinations of psychiatric symptoms. Delirium imitates other psychiatric disorders, leading to missed diagnoses and misdiagnosis. Systematic approaches to patient evaluation and management lead to early detection and aim to reduce patient morbidity, inpatient length of stay, long‐term cognitive effects, and mortality.