TRUTH TELLING OF ALZHEIMER’S DISEASE DIAGNOSIS. Alzheimer’s disease is becoming an increasingly common problem due to population aging. Most of the research on truth telling in relation to diagnosis has been done in oncology. However, although growing, there has a lack of interest about attitudes held among physicians towards disclosing the diagnosis of Alzheimer’s disease. Physicians, family caregivers and patients have different views about it. The reasons most often given for communicating the diagnosis are the right to know, relief of anxiety to know the cause of memory problems, early access to treatment and ability to plan ahead. On the contrary, the reasons for concealing the diagnosis are based on the right not to know, the anxiety associated to knowing the diagnosis and the absence of curative therapies for the disease. The aim of this paper is to report the current state of literature on diagnostic truth telling in dementia, review the ethical principles involved, and finally give a strategy to address the issue.