Among legislative criteria granting the right to practice euthanasia or assisted suicide, there are systematically four major elements. Precisely, any request must be voluntary, persistent, to be well thought and well informed. Such euthanasia raises numerous difficult questions in case of dementia. It also justifies thinking about possibilities that can offer specific arrangements of anticipated demands in such peculiar cases. Empirical experiences show us that it applies with difficulties in practice. Finally, to avoid that a big majority of these demands would find themselves not applied in practice, it would certainly be necessary to add to it structural valuation of advance care planning, and assure its recognition and development. These should not be limited to a single pathological target but would address all of us to increase advance care planning initiation, which remains the most limiting factor of such any early but continuous procedure.