Informed consent is a fundamental ethical concern for dementia researc
h that involves the participation of human subjects. The central dilem
ma is how to obtain valid informed consent from a population of potent
ial subjects who are losing their decision-making capacity while still
providing adequate protection for this vulnerable group of people. On
e model for informed consent for dementia research would be to obtain
consent in advance of the loss of decision-making capacity, perhaps us
ing written advance directives similar to those used for clinical deci
sions on life-sustaining treatments. This article examines the advance
consent model, contrasts the life-sustaining treatment arena with dem
entia research issues, and suggests, that written advance consent shou
ld not be required to conduct dementia research. Instead, an argument
is presented in favor of a more informal advance consent process that
builds upon the existing practice of using subject assent plus proxy c
onsent.