A growing body of evidence suggests that the most common type of dementia in schizophrenia differs from Alzheimer's disease in its clinical features, natural course, neuropathology, neuroanatomical substrates and prognosis. Furthermore, there is some evidence that the risk of developing cognitive impairment and its progression in early-onset schizophrenia differ compared with late- or very-late-onset schizophrenia. The diagnosis and management of dementia in schizophrenia is challenging for both general adult and old age psychiatrists. This article reviews the evidence base regarding dementia in schizophrenia. It discusses the diagnosis of dementia in schizophrenia, its management and prognosis, and identifies some future research opportunities.