This clinical trial will be a multicenter, randomized, double-blind, placebo- controlled, parallel-group study of vitamin E and donepezil in 720 subjects with mild cognitive impairment (MCI). Subjects will be randomized to one of three treatment groups (240 subjects per treatment group): 1) Placebo vitamin E and placebo donepezil plus a multivitamin daily. 2) Vitamin E (2,000 I) and placebo donepezil plus a multivitamin daily.3) Donepezil (10 mg) and placebo vitamin E plus a multivitamin daily.