Proper ethical evaluation of the use of therapy robots in dementia care requires consideration not (only) of the individual patient and their abilities, but rather of the nature of the care relationship and the effects of therapy robot use upon it. Dementia care should be guided by the question of if and how care relationships can be structured so as to preserve and facilitate the personhood of the patient. Kathrin Schuster argues that, for those with advanced dementia, being a person is essentially being in relationships with others, and presents an account of the intrinsic value of successful care relationships. On this basis, it is shown how an ethically responsible use of therapy robots depends upon the specific conditions required for successful care relationships and what this implies for the practice of dementia care.