The pharmacological treatment of dementias aims to improve cognitive deficits, activities of daily living and behavioural and psychiatric symptoms. The weighting of theses therapeutic aims varies with disease progression. Behavioural symptoms may dominate especially in the more severe stages of the disease and may further deteriorate global functional level of the patient. Today there is no causal therapy for Alzheimer's disease (AD). Based on preclinical disease models novel therapeutic approaches are under development that target the beta-amyloid and tau protein metabolism. Some of them aim to inhibit the formation, aggregation and toxicity of beta-amyloid peptides or promote their clearance from the brain. Others inhibit the formation of neurofibrillary tangles or have neuroprotective effects. Active or passive immunisation against beta-amyloid may be a very specific and effective approach. The efficacy of acetylcholine esterase inhibitors (AchEI) in the treatment of mild to moderate AD is well documented. They are first line therapeutics in the treatment of the disease and lead to a delay of symptomatic progression. Memantine is effective in the treatment of moderate to severe stages of AD. The evidence for the treatment of vascular dementia is comparatively weak. However, positive effects have been shown for all available AchEI and memantine. Non pharmacological therapy is an indispensable part of the treatment of dementia patients and should be adapted to the individual needs of the patient in the respective stage of the disease. The efficacy of antipsychotics in the treatment of behavioural and psychiatric symptoms of dementia is limited. These drugs are associated with increased morbidity and mortality in dementia patients. Therefore, their application should be based on a critical and individual evaluation of risks and benefits.