The behavioural problems of people with dementia are often considered as one of the most challenging issues in caring. Special Care Units (SCUs) have flourished since the 1980s with the aim of taking care of dementia patients, usually those with Alzheimer's disease, and in particular for those with behavioural problems. Although lacking a standard definition, SCUs are usually situated within nursing homes and commonly include the features of trained staffing, special programming, a modified physical environment, and family involvement. The costs of SCUs are commonly higher than for 'standard' nursing home care. However, evaluations of the outcomes of SCUs have yielded conflicting results. A systematic review of this evidence is therefore warranted.