One-third of adults aged 65 to 79 report feeling lonely most of the time. Half of those over the age of 80 report feeling lonely often. Other age groups at high risk of chronic loneliness include disabled persons and adolescents. These data are alarming considering that chronic loneliness is associated with depression and poor physical health. Against this background, the ERC-funded Ethics of Loneliness project will explore the moral duties of private individuals and those of states to help protect people from loneliness and to ensure that people can protect themselves. Its findings will be used to develop the first normative theory of loneliness within the scholarly literature and help establish the ethics of loneliness and sociability as a new sub-field within moral and political philosophy.