While dementia is an umbrella term for a range of degenerative brain disorders, many share similar presentations. Nurses are ideally placed to identify those at risk and empower them to access treatment and plan and prepare for their future needs--as such, they need up-to-date knowledge of the signs and symptoms of the different types of dementia to identify risk factors and make an informed diagnosis. This article, the third in a four-part series on dementia, examines the risk factors, signs, symptoms and diagnosis of dementia, as well as outlining lifestyle factors such as diet and exercise that may help to prevent the development of the condition.