Shared Decision Making in clinical practice, concerning patients with dementia, refers to the patient’s, the caregiver’s and the attending doctor’s participation in decision making for issues that affect the patient’s health. Shared Decision Making can also be used in patients with neurodevelopmental disorders, while a conversation for its extension in more circumstances is taking place. Shared Decision Making can favor a patient’s with dementia autonomy, which is believed to be of crucial importance for the patient’s quality of life. A wide range of bioethical dilemmas has been developed as far as the Shared Decision Making in patients with dementia is concerned. For example, to which point should the patient’s participation in decision making be affected by the stage of dementia? Of course, a patient with dementia participating in decisions for every day life matters, could meet severe difficulties concerning medical issues, which are of greater importance and more complicated. Another ethically and legally critical issue is the potential use of Shared Decision Making once dementia or even mild cognitive disorder is diagnosed, without having already characterized the patient as unable to consent. Shared Decision Making also emphasizes that caregivers of patients with dementia should be selected by the patient. However, what should be done if there are more of one interested persons to take the role and the responsibility of becoming the main caregiver and the patient is not willing to choose among them? Should there be any criteria according to which a person would be suitable or unsuitable for becoming a patient’s with dementia caregiver? Shared Decision Making for medical issues could always be a good choice for a patient’s with dementia autonomy and dignity, provided that both the caregiver and the attending doctor respect the patient’s personality and previous wishes and that they are well collaborated with each other.