Informed consent is a fundamental ethical concern for dementia research that involves the participation of human subjects. The central dilemma is how to obtain valid informed consent from a population of potential subjects who are losing their decision-making capacity while still providing adequate protection for this vulnerable group of people. One model for informed consent for dementia research would be to obtain consent in advance of the loss of decision-making capacity, perhaps using written advance directives similar to those used for clinical decisions on life-sustaining treatments. This article examines the advance consent model, contrasts the life-sustaining treatment arena with dementia research issues, and suggests that written advance consent should 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 consent.