Advance Directive for Dementia
Little time to read about the issue and just want a brief introduction and form to get started? Try this one (out of the US) from DementiaDirective.org. They provide simple background information that can be reviewed quickly. They also provide links to media coverage of their form. You later may want to revise such a form as treatments advance or under other circumstances. You may want to add a periodic, repeating reminder to to your calendar to revisit your decisions. The form is not legally binding. It is meant to guide caregivers and physicians.
Country specific reading and resources
April 2019 Dutch court allows euthanasia in advanced dementia cases This appears to be a followup on the same case reported in September 2019.