The European licensing of rivastigmine (Exelon) has made available on the market in the Netherlands a compound with the indication 'symptomatic treatment of mild to moderate severe Alzheimer's dementia'. This paper reviews the results of the studies of rivastigmine and other cholinesteraseinhibitors. It is questionable whether the effects found in these studies have any clinical relevance. Responders, patients with a clinically meaningful improvement, are seen in a very low percentage in both active compound groups and placebo groups. Studies with a duration of six months in patients with mild to moderate Alzheimer's dementia (ad) are probably too short to demonstrate efficacy convincingly.