Alzheimer's disease is common, incurable and disabling. It is expected to grow dramatically in prevalence over the next 50 years. At current, the standard of care for patients with mild and moderately severe Alzheimer's disease includes the use of acetylcholinesterase inhibitors. Donepezil (Aricept) is a highly selective acetylcholinesterase inhibitors with a pharmacokinetic profile allowing once-daily dosing. There is an extensive knowledge base derived from published clinical trials of donepezil in Alzheimer's disease, revealing consistent efficacy in cognition, global clinical ratings and daily function. Donepezil is also associated with additional meaningful outcomes such as reduced risk for, or delay to, nursing home placement. Despite a sense of limited efficacy of this drug class among prescribers, number needed-to-treat analyses suggest donepezil is highly effective at reducing the long-term adverse outcomes associated with Alzheimer's disease.