People with dementia are particularly affected by the acoustic environment. While people with dementia might have normal hearing, they can lose the ability to interpret what they hear accurately. As such, the amount, type and variety of noise a person with dementiais exposed to needs to be carefully regulated, as overor under exposure to noise can cause confusion, illusions, frustration and agitation. This paper exploresthe role of noise on the ability of people with dementiato interpret and understand their surroundings. Examples are provided of acoustical design and management practices that contribute to increased levels of agitation and aggression among residents who have dementia. Guidelines are provided for the acoustic design of dementia care facilities with the ultimate aim of creating facilities that are calming and engaging for people with dementia in residential care.